How To Avoid Structural Issues In Home Extensions with Sam Dean | 118

If you design home extensions, I bet you have hit a

structural problem or two in your time.

In this episode, you'll learn common structural design

pitfalls, how to avoid them.

How to limit spiraling structural costs and stick around to the end where our

guest shares what to expect from a good structural engineering service.

Welcome to Architecture Business Club, the show that helps you build

a better business in architecture so you can enjoy more freedom,

flexibility, and fulfillment.

I'm your host, John Clayton, and if you're joining us for the first time, don't

forget to hit the follow or subscribe button so you never miss another episode.

We're joined by Sam Dean.

He started out as a material scientist and structural engineer, spent a year in

the nuclear industry, then teamed up with his good friend Chris Porthouse to start

porthouse Dean structural engineering.

Sam then got hooked on building business systems and automations.

To cut out the boring stuff and let his team do much better work.

And when he is not solving process problems, he's cycling to work,

playing and watching football or baking crusty bread and homemade pizzas,

which is actually making me feel really hungry, just thinking about it.

So to connect with Sam, you can email him directly at sam@porthousedean.co uk.

So Sam, We are gonna talk about, um, common structural design pitfalls

and, and how we can avoid them.

Groundworks, I think is the best place to start really, isn't it?

So what, what do you find often gets overlooked when it

comes to ground conditions?

Well, everything really, because you don't know what's there until you put

your spade in the ground most of the time.

Uh, you can have a guess and most people, you know, if they've worked

on, projects in the local area, they'll be able to have a stab.

But you ultimately do not know until you've put a spade in the ground,

the, the ground can even change from one side of the site to another.

So there's even a debate about, you know, if you were to do intrusive

investigations, trial pits or something like that, how many do you need

to do to have absolute certainty?

I think it comes down to, uh, an appetite for risk in some ways, because, you know,

if you want to do upfront investigation to limit your risk, it costs.

A lot of people, they're not probably prepared to pay that cost.

It's not something that maybe the architects will feed to them, particularly

on the projects that we work on, such as a single story extension.

You wouldn't expect to have borehole rigs and, you know, these extensive,

uh, geotechnical surveys done in order to establish the ground

conditions on sites like that.

So what usually happens is that the builder gets to site, they start the work.

Presumably they'll allow for some contingency in their, in their quote,

uh, and they'll get to site, they'll put the spade in the ground and they'll

go, whoa, this is, this isn't right.

Or they'll usually, what what happens is they'll find clay.

That's the, the, the big one.

Um, and when there's clay, usually that prompts, um, a building control

officer to say, whoa, hold on a minute.

Um, and then you, there needs to be an investigation.

You need to establish whether there's any trees nearby and things like that.

So all that kind of part of the process, um, can really add to a

lot of stress when it comes to the homeowner undertaking their project.

Um, the builder starts talking about, you know, sometimes extra costs in the

sort of tens of thousands of pounds for what goes on below the ground.

And, uh, having to dig, for example, um, very deep trenches.

You know, sometimes they need to go a couple of meters deep.

And then after that point you're talking about piled

foundations for things like that.

So it's, that is a real tricky one.

We've worked on some projects where, you know, there's been a huge tree almost

immediately adjacent to the extension.

It would be, helpful to, to consider that right from the early stages, you know,

and, and, and, and maybe try to eliminate some of that uncertainty, knowing if

there are large trees on the site that this could really impact the scheme.

So maybe there are certain instances, particularly when there are trees nearby,

large ones, we're not talking about sort of like two and a half meter shrubs,

cherry trees and things like that.

But anything where it gets sort of up to about 10 meters or

over, you know, you, you've.

Maybe, maybe even a little bit less than that actually.

And within probably 20 meters of the, of an extension or something like that,

that might be a point where you go, maybe this is worth the customer's time, uh,

to, to do some exploratory works if they are price sensitive, if it calls into

question the viability of the project.

That's, uh, can be a real sticking point.

The one thing that we have at the moment, which we're rolling out on our projects

is we have like a, a geological report, which is a desktop report based on

British geological, uh, borehole records.

it's never gonna tell you exactly what's there.

Like I said, you don't know whether until you put the spade in the ground,

but it's, uh, it aggregates that data from the bore holes and it predicts

the likelihood of there being such things as clay and things like that.

So it's a bit of a red flag, um, in, in those kinds of

instances, which can, can help.

And it's low cost as well, so,

Oh, well that's good.

That's good to know.

So, um, you mentioned there that there is.

Potential for different ground conditions, even within a fairly small area.

So even within the, the same site itself that we could have,

um, differing conditions in the ground in a relatively small area.

Clay, you mentioned there was something that was, potentially a big issue in

terms of kind of the type of foundations that would need to be specified,

how deep they might need to go.

And you also mentioned there about the presence of trees.

Um, I mean, I suppose the obvious thing there is, at least with the trees, that

we, we do see them above the ground.

I think we can probably safely say that not every single designer, um, will let

the engineers know about the presence of the trees and depending on the type

of service that's provided and when they're appointed, that, that could

be quite problematic, couldn't it?

If you've been, you know, instructed to provide some calculations for an

extension project and, um, maybe you've not been given all the information

about the site and not been told about the presence of, um, a big oak tree or

something in the garden, you know, a few meters away from the extension site.

Yeah, that's right.

Um, I'll give you an example that we had recently where, uh, there was a

tree a couple of meters away, two or three meters away from the extension.

It emerged that there was a tree, um, something like, I don't know.

Maybe 15, 20 meters high, and it was only a few meters away from this extension.

Whether that's clay or not in that situation, that really at an early

stage should be considered when it comes to actually designing the extension.

I think because if, if, if the drawings get to us and everything's gone through

planning and all the rest of it, what, uh, as engineers, what are we actually

gonna do that's gonna help that situation?

there's not really a lot we can do.

That's a really tricky one because it's gone so far down the line that

it's so hard to change course and whatever the outcome really of that

situation, it's gonna cause distress

For the, for the customer.

Clay obviously exacerbates that, but from our angle, and this is why we're

including the geological reports.

If you are looking at a tree 10 meters away, you're probably really

only gonna be concerned about that if you know that there's a,

a likelihood of there being clay.

And that's why those geological reports help because it, it

gives us that trigger to go.

'cause we can actually judge looking at, um, a lot of the

time looking at Google Maps.

You know, we can go on and have a look at the images of the site.

Usually they're three dimensional, if you're lucky, in, in, in

a lot of, um, rural areas.

It's still grainy and they've not really got a lot of detail, but in some of

them you can get a 3D elevation, you can go, oh wow, that's a bit of a whopper.

You know?

We can do that investigation, but we would probably only usually do that

when, when we've got that trigger, which is usually clay, if that makes sense.

So say there's a tree that's been removed in the last year,

depending on the type of tree and the type of soil, could that still potentially

have a, an impact on the, foundation design for a home extension, even

though it's been removed from the site?

Mm-hmm.

comes out to be prohibitive.

And so the builder will say, well, I'll remove the tree.

And you say, well, it, it doesn't quite work like that because the reason why

clay is a problem is, uh, with trees is because of a process known as desiccation,

which is essentially another way of saying the drying out of the clay.

Think of like desert plains where you see all the cracking of the ground.

That's because of desiccation where it all starts to, unravel.

So what happens is when you remove the tree, you've got, um, the root

system has been extracting water from that clay for a number of years.

And so that clay has a lower moisture content relative to

the, uh, surrounding clay.

And it takes up to three years for that clay to actually normalize.

Wow.

So you, you say to people, you can move, remove the tree, but it doesn't

affect the requirements until, uh, you know, the three year mark probably at

least, uh, after you've removed the tree.

That's quite surprising.

Yeah.

I'm glad I asked the question now.

Yeah.

It's a good one.

Yeah.

So thinking more about some of the, the pitfalls when it comes to

maybe the, the interior of, say a home extension renovation project, down stands

in ceilings is something that I imagine that comes up as an issue quite often.

What are your thoughts on that from a structure engineer's perspective?

It can be useful to know if the client expects a downand.

Um, sometimes there's, uh, there can be a trade off u usually people

don't want down stands, they don't want to see a beam in the ceiling.

They want a flush ceiling.

Um, and so we try to design for that kind of as a default.

It's rare that somebody would go, oh, I, I'd rather have a, you know, a,

a down, a down stand in the ceiling.

So we do try to optimize for that.

But if, if there was a downand expected, you could potentially get away with a

lighter weight steel in certain instances.

you're probably not gonna get savings by having a downturn most of the time.

It's only in certain specific instances.

So really what what happens is when people come to us, builders or

such, like where do I put the beam?

Because we don't really say where exactly the beam goes.

And I think that's messes with people's minds a little bit that, you know,

like, you are the engineer, why are you not telling me where the beam goes?

And, and the answer usually is, it doesn't really matter

in the context of our design.

So our design is valid whether the beam is lower or higher.

So you can do either, That is a discussion really, which needs to take place between

the homeowner, the architect, and the builder in, in my point of view because it

comes down to cost in a lot of instances.

It depends often on the span direction of the floor joists.

So if the floor joists run into the wall, then it can be a bit of a big deal because

if you need to, if you imagine that you've got floor joists running into a wall,

and then you are removing that wall and you need to push that bee ups so that the

joists, uh, fixing into the side of the beam, you often need to cut those joists

to allow for the installation, allow room for that beam to, to, to sit there.

That can add a, a decent amount of cost for the customer, um, which they

might be prepared to pay if they, they.

Happy with the aesthetics, but again, it really doesn't make much difference

when it comes to our engineering design.

The size of the beam is going to be the same, whether it's got the

stick, the joist fixing into the side, or whether the joists are

just sitting on top of the beam.

That example you've described, say where we are adding an

extension on the back of a property, we're taking out a proportion of the

rear wall, maybe all the rear wall, maybe we've got like a sort of a goalpost

or window frame type steel arrangement where we've got columns either side

and a beam running across the top.

So from a structural engineer's point of view.

It's fairly cost neutral in terms of the steel cost, whether, whether that

beam is below the ceiling line of the extension or whether it's pushed

up and hidden within the ceiling.

But the factor to consider would be, depending on the span direction of those

first floor joists, if they are running into that, the web of that beam, then

potentially there's a bit more work, um, with the installation costs to basically

kind of cut those joists back and then fit them, fix them to the web of that steel

versus the beam just running below them.

Perfect.

Yeah, absolutely.

You've gotta view this from the, from the point of view of each party to, to, to

the discussion, you know, and the builder.

They usually don't wanna do work.

Like they, I don't, I don't want, like, they don't wanna

do more work than is necessary.

Let me rephrase that.

I'm appreciate there, there will probably be some builders watching me thinking,

um, but yeah, um, builders will tend to want to avoid doing work and so they

might advise the client not to do that.

Uh, but the client might want that and not realize that they can have it.

Depending upon who's approaching it, can give them different advice.

Um, and the client needs protecting, um, because they don't know.

They don't know what that is all about.

They don't know about Joyce fixing into the side or the structural design

implications or this, that and the other.

But, you know, if you go back to trying to make the project

smooth from start to finish.

You know, and, and budget, which is usually a very important

thing to discuss at the, at the early stages of the project.

If that is budget dependent, then that should probably be

considered early on as well.

Um, it, this might save you a few thousand pounds if you choose to have downand.

Is that okay?

And because it's trade offs, it's always trade offs.

Um, people often say, well, homeowners often say, can I do this?

And you go, yeah, but it'll cost more.

You know, if you, if you're willing to pay for it, yes, it, it can be done.

It's just whether or not you are prepared to pay for it, you know?

Yeah.

Most things can be done.

I think that was interesting what you said about them being protected, that

there can be a variety of different stakeholders, different people

involved in even a relatively modest.

Home extension project.

You know, obviously the client, an architect or architectural

technologist, architectural designer, somebody doing the architectural

design work, structural engineer.

Usually nearly all cases, there's a structural engineer involved.

There's a piece of steel or something that needs to be sized or calculated, and

then there could be other consultants as.

And then depending on who's involved in those work stages, like I think a classic

thing would be that, um, on a relatively straightforward kind of everyday home

extension project where the clients may be commissioning the architects to

only provide pre-construction services.

So like our IBA stage to stage four, say, planning, building

regs, that sort of thing.

They might not then be employing them to see it through the construction

phase, you know, as a contract administrator or project manager.

So when it then comes to making those type of decisions about, for instance,

the height of the beam installation, where it goes, most instances something will

be, will be drawn, there'll be something that specified the architect may have.

Draw a cross section cutting through the back of the house and showing

where they want the beam to go.

But then if they're then not involved in the construction phase, their

influence over the final design is then somewhat limited because then if the

contractors, then the one that's if got the most influence over the client, the

homeowner, and they may be like, most good contractors these days are very, very

busy and very booked up many months ahead.

Maybe the more appealing to them to do it the easier way, which

might not necessarily be the best finished job for the client and might

not be quite what they expected.

Um, I mean, I know we could open a can of worms here with

Building Safety Act, couldn't we?

Which I'll, I'll try not to do that, but those design decisions should

be then coming back to, you know, whoever's then fulfilling that.

Principal designer role.

So in theory, maybe it should come back to the, the architects if they are

going to change the position of a beam.

But I imagine there's an awful lot of cases when that doesn't

happen and it just, you know, there can be some changes made.

you know, you've hit on the, the crux of, you know, what

is an architectural consultant?

What, what are, what are, what is their responsibility?

I mean, the responsibility of an architectural consultant is whatever

they agree to contractually.

Like, if, if they just agree to produce planning drawings for you

and there's no sort of oversight on things, they'll, they'll, they'll,

they'll literally just do exactly what you say and then go bye byes.

You know, and, and, and that's it.

And wash their hands.

The role of, uh, an architectural consultant, uh, doing the full,

the full project is a, is is a de facto project manager.

You know, so, so the value to the customer of having that support right

the way through the project is something that I think, um, yeah, probably a

lot of homeowners don't understand.

As you touched on, um, you're seeing this a lot more with the,

uh, principal designer role.

A lot of homeowners are coming to us at the moment and say, please, can you

sign this principle designer, uh, form?

And the reality is we are not the principle designer.

We're not.

We are designing a very, very small part of the project, but because we are

designing something in inverted commas, they, they, they assume that we're gonna

sign that, but it's not appropriate for us to sign that because we've not

had the holistic view on the whole design, because there's many different

parts to the building regulations.

I think maybe at the, you know, the point of sale, if you wanna call it that, or

the, the upfront communications, uh, I'm, you know, I'm sure you have a, a

much better understanding of, of, of what goes on the media, but that, that

sometimes could be a difficult sell if they just want, uh, planning drawings.

I think, um, because often these, the, the smaller projects are

often very cost driven, that there is, there often can be a finite,

very finite budget to work with.

And I think because

the rate that the cost of construction has increased in the last few years

for variety of different factors, um, you know, rising material costs

with Brexit and then, you know, COVID and lack of supply of labor.

Um, so many different factors at play that have affected that, that you, you

know, I've had conversations before with architectural clients who, where, you

know, the neighbor had had something done a few years ago and then they've

gone out, they wanna do something similar, and it's like, oh, well, when

the neighbors had it done, it was.

80,000 pounds and it's like, yeah.

Whereas now you know, it, we could like double that and maybe then some, you know,

um, even just in the space of a few years.

So, um, yeah, it's, it's very difficult.

I think for those, um, those smaller projects.

It really is from a construction cost point of view.

Um, bringing it back to design though, Sam, could we talk a

bit about, um, cantilevers, so sort of cantilever designs.

I mean it can look really cool, but do you have any tips on that so that, um,

you know, we can design something that's buildable that doesn't break the bank?

Yeah.

It j it just makes me smile because I, if there are any structural engineers

that do end up watching this, I'm sure that they'll, they'll just

be chuckle to themselves at this.

I think what it does is it touches on how useful it is just to have a

little bit of structural intuition.

In the architecture space, you know, because it can really drive up the cost if

you, if you, if you're doing things which are not necessarily not feasible, but

just add costs that the, the customer just didn't expect and it happens all the time.

so there's a, a sort of rule of thumb when it comes to cantilevers.

Obviously a cantilever sticks out a certain amount.

Let's say it's one third of the total length of the beam.

You need two thirds to be anchored basically.

So you've got the pivot point.

Then you've got the sort of anchor and usually the distance between those

two points needs to be double the length of the, the sticky outie bit,

let's keep it simple for math's sake.

Um, so if we've got a one meter cantilever, let's say we've got an

extension and maybe the first floor part of this is cantilevering out by meter,

then the length of that beam that's embedded within the building would

need to be an additional two meters.

So we, as a rule of thumb, so we might need a three meter long beam to

facilitate a one meter deep cantilever.

exactly.

Yeah.

There are certain projects where, you know, you see sometimes even more of a.

Cantilever than he is actually available to actually anchor it to, and that's gonna

result in very, very high steel sizes.

If, if, if it's possible at all.

what's quite popular at the moment is, is, uh, bifold doors,

um, at the corner of extensions.

Bifold doors have a bit of a wow factor.

You know, they, they make the, the outside come inside and, and, and, and blur that

boundary between inside and outside.

They, they're lovely.

They're absolutely lovely and it can make your extension look really wow if

you've got a cantilever on the corner.

'cause you can open that up in, in both directions and the

whole corner just looks like

it's floating,

Let's say it's a single story, flat roof, rear extension.

It's a kitchen diner on one of the rear corners.

We've got bifold doors that are on, that are spanning across the corner.

So we've got two walls meeting each other where we've got the bi-folds and

the roof is cantilevering over, over that corner where the bifold doors are.

And there's no, in this example, there's no column in the corner.

It's just cantilevering over.

What can happen is that you get too long bi-fold doors

and that is not really gonna lend itself to an efficient design.

'cause usually what happens is you have one of the beams, which is actually the.

The cantilever.

So it's the, it's the, the bit which is sort of rigid and that

supports the end of the other beam, which is coming out to meet it.

So that's just sitting on that.

So all of the strength is derived from that one beam.

Usually what an engineer is gonna look for is they're gonna look for

one side, which is shorter cantilever.

So that shorter cantilever can enable you to have a much bigger

cantilever on the other side.

'cause that's just a normal beam.

So you can probably have like a relatively efficient cantilever corner post situation

if one of the cantilevers is, let's say one meter or maybe pushing it, maybe go up

to like 1.5 meters and the other one can be three meters or something like that.

so that is, is eminently doable As long as, as I say, you know, with the

one 1.5 meter section you have that.

Fallback of the two and a half, three meters of wall that you need

to kind of anchor that cantilever

Are there other ways around it?

So let's say that along the wall length from one of those sides that you didn't

have enough length for, like, you know, the, the beam to continue to like, I

dunno, 1.5 meters or something of the, of cantilever and then it needed to extend

by sort of three meters into the wall if we didn't have three meters there.

Are there other ways to work around it by, I dunno, having some kind of like

column or something hidden within the wall that's attached to the end of the beam.

Are there any other kind of like ways that you as engineers

can kind of work that problem?

Are you sure you're not an engineer?

I'm not, but I've designed several hundred home extensions

over the last decade or so, so,

of course.

You know what you're talking about.

Um, yeah, so, so, so you, you exactly as you describe, you usually,

um, would have a, a system of two columns, because what happens is, is

that if it's a bit like, it's, it's like the classic lever arm thing.

So when you, when you're having to leave or something, it's better to be on the

long end than it is on the short end.

The short end is where you get that prying effect, you know?

So if you imagined that, but you had one column, which was kind of

the pivot point, and the other was the anchor, that's got to resist a

huge amount of multiplying force.

It has this multiplying effect and that needs to be dealt

with, uh, in the foundations.

'cause the foundations need to be heavy enough to counteract that uplift.

So if they're, they're pulling up on one of the columns, it's also pulling

up on the foundation and you need to make sure that that's anchored.

'cause we just work with numbers.

So we look at it and we go, yeah, that makes sense.

But to the external observer, they're going, why the heck is that column

got such a massive foundation?

And so you need to explain why you, why you've done things.

It doesn't make sense.

'cause usually it's got not got a lot of load going on it, it might just

be, you know, just effectively not supporting anything in certain instances.

What about, um, adding an extra story?

I mean, that can be a great way to add extra space to a property, but

it's not without its challenges.

What are some of the pitfalls there?

Foundations tends to be one that crops up.

One of the things that I don't really understand is why it does crop up as

a problem so often because, in the building regulations you have, um, like

some strip footing widths recommended for certain ground conditions.

And the reason why these are in the building regulations is they don't want

a structural engineer to have to do it.

So usually a standard strip footing width is about 600 mil.

That is usually good on, on reasonable ground, not, not even necessarily

very good ground, but reasonable ground for up to about three stories.

Wow.

So in most cases, you know, a 600 mil footing is going to be okay.

But it's worth checking if you are considering putting an extra

story on top of some existing, uh, you know, single story work.

In some particularly old buildings, there's no foundations.

You've just gotta wall sitting on, uh, the earth.

Uh, and maybe that's 'cause it's really good ground or maybe

it's just not very well built.

It really is something which could affect the feasibility of the project.

'cause you might end up having to.

Underpin all of that, uh, all of those walls with proper

foundations to facilitate going up.

So it is another one of those things that's worth considering

earlier on in the, process.

There's not a lot involved with it.

It's usually just digging a hole.

Right.

You know?

Uh, which isn't something I like to do very frequently.

It's not one of my favorite pastimes.

I prefer baking bread.

But it is doable.

If, if, if, you know, you get a, a contractor on, on site with a little

digger or something like that, it's not a costly exercise to do that.

The other thing that comes up is when there's like existing steel work.

Quite often is you get a single story extension, which has been expanded out

from a, like a two story outrigger.

So in a lot of the older properties you have these out, what we call outriggers.

I don't know what is that a term you

would use?

Yeah.

When people are extending, they'll usually knock out the side

wall and extend out to the boundary.

Or maybe in certain instances they'll exp expect expand out to the rear as well.

Um, and what that requires is to support the second story outrigger at the top.

so that needs steelwork, which is something that, you know, we

would do and all the rest of it.

when it comes to 10 years, 15 years down the line and somebody goes, I

want to extend my loft conversion out into that space, oh, where are the

structural design calculations for?

Well, oh, you moved into the house and the old owner had them and you can't contact

them and nobody's got any documents.

And even if you did have documents, is it already gonna be designed for a loft?

Probably not.

So that again, is something which can really affect the feasibility of a project

if you're gonna be building onto, uh, existing steelwork can be stressful for

people, particularly when you go back and say, you know, there's really not any

way that I can really substantiate this.

When we produce our own designs.

That's ours, that's our specification.

We know exactly what's gonna go in and we can specify exactly down to

the finest detail what's gonna go in.

But with somebody else's work, you have no idea what's gone in.

You don't even know if you, let's say you had a, some structural design

calculations from, um, way back.

There's not even any evidence necessarily that it was built in that way.

'cause builders do tend to sort of interpret these things in their own way.

So it, it really is a difficult situation.

I've been involved in a project like that

exactly that you've described.

Um, exactly that scenario where there was a prior extension on the property.

The rear of the building had been sort of opened up, you know, made this sort of

classic kitchen dining, living room space.

And then later years later they wanted to then add a loft and.

It was then that whole thing of like, well,

where's the calculations for the original steel that was installed?

Was it, was it installed as per the couch, if you've even got them.

And then the thing of, well, you do realize that, you know, if you do want

to do this work at the second floor level, add this loft that, we're gonna

have to expose this steelwork downstairs.

And potentially there was one or two of those beams that may

have had to have been replaced.

So it was gonna end up meaning that in order to do the loft, they also

had to do significant renovation work, significant structural work

at the ground floor level as well.

Because exactly what you described, it wasn't factored in when

they did the extension prior.

And, and a lot of the time when people have that kind

of work done, they're not thinking about what might come next.

They're not thinking about the next property owners.

They're not.

So documenting what's happened is not a priority.

I mean, that's understandable.

Mm.

you know, it would have to be a very, you know, mindful and

generous person to say, Hmm, somebody might be mo moving into this property

in a few years time and they might need this information and they might

need to know exactly what's installed.

So I'll take photos of everything and make sure it's all documented so that when the

future owner does come around to doing a loft conversion, um, they'll be able to

pass all that to the structural engineer.

I can tell you, I mean, there must be zero times that

Yeah.

That's, that's, that's never gonna happen, is it?

Yeah.

Unfortunately.

I think, um, that's another point.

I suppose just thinking about this, so in terms of prevention,

you've mentioned that, um.

Some of these problems can be avoided if we do some ground investigation.

So maybe spend a few hundred quids on a local contractor to come out,

dig some trial holes, to have a look at those footings and maybe some

ground investigation before, blazing ahead with the projects where you're

looking at adding a story or, or converting your loft and adding a

big dormer or something like that.

Um, you also mentioned there about if there's been any other prior works,

the existing steel work, existing structure that's there already.

We need to have an understanding of what that is because then there could

be additional cost to kind of put that right, or at the very least to expose it

and check it to make sure that what was specified was, was what was installed.

The other thing I guess is.

Let's say you're in a situation where you were planning to say,

I dunno, add a second story above an existing part of the building.

Maybe it's single story, you can add a story above.

I presume the other thing would be like looking at what it's built out

of, you know, if the conditions or the footings are, I dunno if he's the right

way to describe it, but not sufficient to just it be a Yeah, no problem.

Just stick another story on top and it doesn't matter what you build it out of.

Um, I recall a couple of projects in the past where it didn't stack

up to, to build it in a masonry cavity wall construction as per the

existing building that was there.

But there was a way to make it stack up if it was in a lighter weight construction.

Is that something that you come across quite a bit as well, where

you'll be, you know, if someone's adding a story that you might say,

well, I. You need to do it timber frame or you need to do it something

lightweight in order to make this work.

Not too often, because most of the buildings in this country are built

using block brick and block masonry.

It seems to be a cultural thing.

One area that it does happen sometimes is new housing estates 'cause new hou, newer

housing estates can have timber frame.

Yeah.

Um, and it's quite an easy check really, you know, you'd find an

external wall ins inside your house and you have a bit of a knock on it.

And usually that'll give you a decent indication of whether it's a timber frame.

But even in, you know, those kinds of situations, you can get around

it by basically building posts.

We've done that before.

You essentially just build the, the new building on top on

posts and try and incorporate those in the existing structure.

It's expensive.

There's no other way to, to, to say that.

So, um, it is probably one thing that's worth having a look at, but it's not

something that we come across very often.

But again, you know, you're talking about return on investment.

What kind of investigation would it take to figure out whether

it's a timber frame wall?

Not a lot really just breaking out a hole in the wall if you feel so inclined,

which you could do on a Saturday afternoon while watching the football if you wanted.

Those are kinds of investments that you can make early doors

that that can help a lot later on.

Have you got any tips in particular that you'd like

to share about, um, avoiding or minimizing those unexpected costs?

I think we've touched on a few of these ideas already, but could

you maybe summarize some of the things that we've talked about

Yeah.

cost saving or, or avoiding the spiraling costs?

Yeah.

So we've talked about the ground, haven't we?

Which is a big one.

I mean, you know, when you're talking about how much could potentially

get added to the, the cost of a project, that is a big one.

Exploratory investigation can be helpful in certain instances when building on top.

Although it's not something that happens very often and it can be

dealt with through the natural course of the building process.

There's a couple of little scenarios that I can think of, um, additional to that.

there's one that we get sometimes where, um, there's like a single

story extension and you have a series of, uh, French doors, just a

series of like three French doors.

And it's not very efficient to do that really, so masonry is.

Very strong when it comes to compression.

So when it's had four supplied vertically on it, but when it's

sort of exerted by wind load on the side, it's not very strong.

And so small sections of masonry with doors on the side is quite vulnerable.

Um, and so in those situations, what we tend to do is we install

something called a wind post.

Again, it's another of those situations where it's like,

what's this post doing here?

This is baffling.

it's not gonna break the bank, but it's gonna raise eyebrows.

It's gonna raise eyebrows, is the best way that I could explain it

a better way to sort of do that.

And again, you know, you, you talk, I'm, I'm venturing into

architectural territory because.

You know, I, I'm not the determinant of what, of taste or anything like that.

I'm an engineer.

I, I deal with the practicalities of the engineering, but to me, uh, um,

a bifold door over that, over those treble doors would look far better and

it would probably cost less ironically.

Um, because you've got less of this fiddly steel where you've just got a beam

that just goes straight over the top.

The other situation is when you are effectively taking out

the whole rear wall of a house.

What people don't tend to think about is, when you are putting a beam over the back

of a house, it's gonna take a lot of load.

It's gonna need something pretty chunky to support that at the end.

Um, that's usually either a brick pillar or it's a masonry column.

and that needs to not only resist the vertical forces, but it needs to re resist

in a lot of cases, the, uh, horizontal forces which come as a re result of wind.

Uh, now we can design, um, masonry pillars to to, to accommodate that wind,

but usually they need to be quite deep.

So we have a sort of rule of thumb where.

You know, we usually we're gonna be able to make it pass, which is if you

have 1.5 meter length of masonry in total across the back appears at both

ends of 750 mil or something like that, you're usually gonna be okay.

Um, so again, it's have those discussions early on because if the

customer's happy with that kind of impact on the aesthetics, it can save

them quite a bit of money having those columns, if they were steel, that can

lead to escalated foundation costs.

And so there's knock on impact of that.

So that brick pillars, uh, versus this frame across the back can add, can be a

difference in several thousand pounds?

I would, I would imagine in certain instances.

One, one of the things that I think architects that we work with maybe

haven't thought about sometimes is.

You know, when, when you're extending out into the single story, what, what

you quite often doing is you put in, um, a kitchen there so you could, uh,

because a kitchen unit is 600 deep, you could potentially do something quite

clever with the kitchen units where it actually forms part of the kitchen

unit and it's not distinguishable, architecturally, I dunno, you, you guys,

the architects, you're the clever ones of how, how to do that kind of stuff.

But I think you understand what I'm getting at.

It doesn't have the same impact on the flow of the room if it's incorporated

into the kitchen units because they're that, that kind of depth anyway.

And that gives you practically your 750 mil.

Um, so that's an option to do it on one side then, you know, if,

if they're happy with the other side, maybe you can make that work.

And that's a discussion worth having.

What about structural engineering services generally?

I mean, what do you think we should reasonably expect from a good

structural engineering service?

Responsiveness.

I don't think there's anything worse than sort of things, you know, from

the customer's point of view than being on site and not being able

to contact an engineer, not being able to get any answers, waiting

ages for documents to be delivered.

Um, just having no visibility of it.

I imagine maybe with the exception of, you know, having kids or

something like that, that.

Having a project like that is gonna be one of the most stressful things

that you've got going on in your life.

You hear some, some stories about things that have happened.

So, you know, you, you want that team that you know you're gonna be

able to get on the end of the phone.

One of the other things which doesn't really, and and probably ties into the

responsiveness is, is just the quality.

You know, uh, make sure that it's properly checked and it's been through a proper

process and things are clearly stated.

Um, you know, and clearly communicated that the resources are available and,

uh, to, to, to the, to the team on site.

But quality is a difficult sell sometimes because you only know

quality when it's not there.

You only know it when it's not there when you've had a bad experience.

That is the only time you would appreciate a. Good experience.

And a lot of the time homeowners, they might only do one, they probably, most

of them will only do one, one or two at most of these projects in their lifetimes.

So there's lucky ones and there's unlucky ones, you know, and, and, um, as an

architectural consultant, I would want to know that, I could just basically say,

look, these guys can do a decent job, use them and not have to worry about it.

Um, I think one of the advantages, we in some ways kind of fill in those gaps.

You know, if, if, if there is an architect, an architectural

consultant who's, um, just doing the planning phase, it can help to have

us there because we are supportive.

So the customer, we're not gonna hang them out to drive.

There's a situation which needs jumping onto.

We will jump onto it to make that go through.

'cause it's in no one's interest for people to leave with a

dissatisfied taste in their mouth from, you know, using our service.

So, responsiveness, quality and collaboration.

Another of the things I hear is, you know, I was working with an engineer

and I asked them to change something and they just said, no, that's how it's done.

We don't do that.

We don't do that.

We don't, we tell our guys to consider whatever is being proposed.

'cause a lot of the time.

It comes from builders, you know, they'll, they'll propose to do something

slightly differently and they might, might have a, a good idea for how to

save some money and things like that.

Um, we do our best to try and accommodate all these d we talked about the

different stakeholders in the process.

You know, the homeowner, the builder, and we try to satisfy everyone and interpret

and look at things from their angle.

But we're not always gonna get that perfect.

And that's why we offer, um, a free change request in our service so people can

come back and if the builder does want to make a change, they think they can

save some, some money, or the homeowner wants to tweak a window or something

like that, then they can do that.

And it, it doesn't add to the cost.

What's the main thing that you'd like everyone to take

away from our conversation today?

It's, it's, it's mainly about quality.

You know, I think that there are certain things that you, that

are indicators of quality, um, and sometimes it's worth paying a

little bit extra for that quality.

My granddad used to say to me, pay cheap, pay twice.

And, you know, throughout my life, I've ignored that advice, you

know, on, on several occasions.

I've, I've, I've bought something thinking, I mean, that's cheap, you

know, bought it and then ended up having to go and, pay for it again.

So I think that that's the main thing that I would take away is, um,

look for the indicators of quality.

Um, and usually kind of like a transparency, I think is, you know,

if somebody's very transparent.

That is a quality in itself.

But if, if, if somebody, like, like we were talking about the planning phase,

and some, a consultant restricting themselves to the planning phase.

If they're saying, I am, I am only doing the planning phase,

they're being transparent with you.

They should be transparent about what that means, you know, for you.

Um, so look for those indicators of quality, uh, and it could be, uh, a

good return on investment in the end.

Um, we've covered quite a lot, but was there anything else you

wanted to add that we've haven't covered?

a lot of discussion at the moment, and I, I think you've

mentioned that you've had some podcasts on, on the topic of ai.

As we record, you know, there's been, um, you know, several recent.

Quite dramatic upgrades in some of the large language models,

graphical interpretation capabilities of, of some of these models.

Um, graphical, uh, production, let's be honest.

It's hard to really know where this is heading.

Uh, all of this, um, one of the architects that we work with has

mentioned that they've been receiving inquiries, which have actually had

architectural information produced by, um, the likes of chat GPT.

it's kind of a, a difficult, it's difficult to know where this ends up.

I, I'm not, I don't have any answers, unfortunately, but it's an

interesting topic and, you know, I, I feel like it's gonna be something

over the next couple of years that's gonna be talked about an awful lot.

We, we actually set up a. Uh, an AI review service.

So I think one of the things that's gonna probably crop up is, um, if things

are produced by ai, I think building controls might eventually say you

need that signed off by an engineer.

Um, so we've, we've, uh, launched a service to, uh, review AI information,

which is useful for us anyway, just to see how things are progressing, how,

you know, how long is it going to be before the AI can do the structural

designs and things like that.

So something to, to think on.

I think that you're absolutely right.

I think it's, it's a hot topic already and it will continue to

be for the foreseeable future.

Um, I think you've given me some ideas for some future podcast episodes from

what you've said, Sam, because um, I think it is a topic that warrants

more discussion for sure, how it's kind of impacting the industry.

Um, yeah.

'cause there's definitely changes that are already happening and

there'll be more changes afoot in the next sort of year or two.

Sam, I've got one more question for you.

What's one resource that you use in your business that you couldn't live without?

So this could be a website, piece of software, an app, a gadget,

a book, a podcast, even any, anything that springs to mind.

Absolutely.

Yeah.

We, um, use this, um, it's actually intended as an IT

support management system.

Um, but because we are kind of tech tech-minded, we try to use

automations and techy things like that.

Uh, it kind of suited us and it has defined workflows in it as well.

But it's this, uh, piece of software called Jira Service Management.

it's like the skeleton of our company.

It's a, it's like our backbone.

It's like everything has to flow through it.

Um, and we actually have contingency plans for, for if it was to go down, because

that's what responsible businesses do.

You know, they identify these because this is a vulnerability

that we're talking about.

If it's, if it's, if it's something which is delivering for you, it's a risk,

it's a vulnerability for the business.

Uh, so as part of our ISO 9,001 accreditation, we have, you know,

these backup plans for, you know, what if, what, what do we do?

How do we receive emails?

How do we, how do we do our workflows?

How do we do our checking?

Um, and so yeah, that is absolutely crucial to our business.

Thanks for that, Sam.

Um, this has been a pleasure.

I've loved nerding out about, um, structural engineering for an hour.

It's been been great.

Um, where's the best place for people to connect with you online?

So probably our website, uh, which is www.porthousedean.co uk so

yeah, I, that's pretty much where, where most of our communications can be found.