New Build lofts - 'very difficult' to convert as opposed to traditional?

buel10

Hi (again),
We have bought a new build house and the developer has consistently been at pains to point out that nothing more than 'empty suitcases' should be stored in the loft and I really had to chase for dimensions of the available area. However, after initially reluctantly quoting £80 for his joiner to lay some boards in there, there were four boards laid and no extra cost, which I am grateful for.
Since then, I have been asking them for specifics on weight and, if in the future, I may want to convert the loft, if this were even possible due to the weight issue.
Ultimately, they put me on to the roof truss company and he replied with the following:

Weight
As discussed earlier the below standard loads is what has been allowed for on your trusses: (image below)

1 kilonewton is equal to approximately 101 kilograms. 
Conversion:
Most attic conversions as far as i'm aware are done on traditional constructed roofs. In terms of trusses you are not able to convert, however, I am aware of structural engineers being able to specify a design to be able to do this but it is very difficult. Therefore I would recommend approaching a structural engineer to see if it is feasible. If not, the only option would be to remove the existing roof structure and replace them with attic trusses. 

I am a layperson and know nothing about lofts.....so is this 'new type' of roof trusses a standard thing now with new builds?
Photos of said loft are below:

ashe

From the photos it doesn’t look like there is enough space to convert after you add insulation, plaster, flooring etc and the roof will need support 

it would probably be cheaper to buy a larger house 

ElephantBoy57

buel10 said:

Hi (again),
We have bought a new build house and the developer has consistently been at pains to point out that nothing more than 'empty suitcases' should be stored in the loft and I really had to chase for dimensions of the available area.
Since then, I have been asking them for specifics on weight and, if in the future, I may want to convert the loft, if this were even possible due to the weight issue.
Ultimately, they put me on to the roof truss company and he replied with the following:

The supported weight would be from the structure, not just the trusses. Not sure we can tell you what you want to know from those photos. You need a structural engineer and some quotes. What is the measurement from the floor beams to the center point of the roof?

buel10

ElephantBoy57 said:

buel10 said:

Hi (again),
We have bought a new build house and the developer has consistently been at pains to point out that nothing more than 'empty suitcases' should be stored in the loft and I really had to chase for dimensions of the available area.
Since then, I have been asking them for specifics on weight and, if in the future, I may want to convert the loft, if this were even possible due to the weight issue.
Ultimately, they put me on to the roof truss company and he replied with the following:

The supported weight would be from the structure, not just the trusses. Not sure we can tell you what you want to know from those photos. You need a structural engineer and some quotes. What is the measurement from the floor beams to the center point of the roof?

Thanks for this, you're probably right.
Height is 2.5 metres.

Doozergirl

They've been using modern trusses like that for many years now.  Traditionally, yes, those trusses are very difficult to convert and you used to have to replace the roof! 

There is, however, an aluminium system that is a dream to work with, that converts the modern truss to attic trusses.  The costs are higher than converting a traditional roof, but those are costs that the developer saves by using those trusses in the first place. 

https://www.telebeam.co.uk/

We've just done one and it's so clever.  I'm a big fan. Just seeing if the guys have any photos.  

 

AdrianC

There's two issues...

First is the available, usable space. Your photo is a perfect illustration. It's just a forest of small timber. You can't remove those, because they're structural.

Second is the weight loading. Your quote about "empty suitcases" is a perfect illustration. Just think about the weight of a load of plasterboard, plaster, wiring, plumbing, furniture, and a couple of people... Or even of boxes and boxes of old books and magazines stored up there...

Of course, they both come down to the same thing. Those trussed roofs are cheap. They come onto site pre-assembled, and they go up quickly. They use very little raw material.

Doozergirl

I'm glad all the full time builders and structural engineers are commenting on this building related question to tell you what can't be done!   🤔

Forest of timber: 

No longer a forest of timber, and my baby boy! 

You only need to open a few rows of tiles and slide the aluminium beams in, which clad to the sides of the modern trusses.  Then you alter the woodwork inside to become attic trusses.  

This loft is probably a bit bigger than yours as you can see the apex is higher than 2.5m, but this is live proof of a simple system that works beautifully. 

AdrianC

Dooz - I don't think anybody said it was impossible... Of course it isn't. The point was that it just isn't that simple. As you put it yourself...

Doozergirl said:

Traditionally, yes, those trusses are very difficult to convert and you used to have to replace the roof!  

So what sort of cost does that beam system add in, compared to starting with a roof that doesn't need trusses removing?

Doozergirl

AdrianC said:

Dooz - I don't think anybody said it was impossible... Of course it isn't. The point was that it just isn't that simple. As you put it yourself...

Doozergirl said:

Traditionally, yes, those trusses are very difficult to convert and you used to have to replace the roof!  

So what sort of cost does that beam system add in, compared to starting with a roof that doesn't need trusses removing?

It was you said that you couldn't remove the small forest of timber after I'd said that you can.  

Every building project is different.  The beams for this cost £8,600 but there are steel costs and calculations in virtually all lofts and most old lofts still
need the rafters adding to meet building regulation depths for insulation.    This was a lot cleaner job than an old house and there's no surprise renovation work involved, so it's a lot simpler than working in a traditional house with a traditional loft.    It totally depends on the house. 

KPyro

Doozergirl said:

AdrianC said:

Dooz - I don't think anybody said it was impossible... Of course it isn't. The point was that it just isn't that simple. As you put it yourself...

Doozergirl said:

Traditionally, yes, those trusses are very difficult to convert and you used to have to replace the roof!  

So what sort of cost does that beam system add in, compared to starting with a roof that doesn't need trusses removing?

You said that you couldn't remove the trusses after I'd said that you can.  

Every building project is different.  The beams for this cost £8,600 but there are steel costs and calculations in virtually all lofts and most old lofts still
need the rafters adding to meet building regulation depths for insulation.    This was a lot cleaner job than an old house and there's no surprise renovation work involved, so it's a lot simpler than working in a traditional house with a traditional loft.   

Oooh that's cheaper than I thought, I was under the impression telebeams added £10k+ on to a loft conversion.
Do you have a sense of what extra this ran you compared to a more standard loft conversion project? Obviously the telebeams cost you more, but it sounds like it may also have saved you in some areas?

It's a project we may be looking at taking on in the next couple of years.

RelievedSheff

Doozergirl said:

I'm glad all the full time builders and structural engineers are commenting on this building related question to tell you what can't be done!   🤔

Forest of timber: 

No longer a forest of timber, and my baby boy! 

You only need to open a few rows of tiles and slide the aluminium beams in, which clad to the sides of the modern trusses.  Then you alter the woodwork inside to become attic trusses.  

This loft is probably a bit bigger than yours as you can see the apex is higher than 2.5m, but this is live proof of a simple system that works beautifully. 

That's an interesting system and one I had not heard of. Thanks for pointing that out.

This is something we would consider in the future with our current home. Our loft space is huge and would make a cracking master suite. We would have to lose the single third bedroom to create the stairs up there so would still end up being a three bedroom house but it would be two good sized doubles on the first floor one being the current en suite master, and then a big master room in the loft with dressing area, en suite and sitting area.