Wood vs. Steel for Dormer Loft Conversions: A Debate with My Architect

[mariohi]

Hi everyone,

I'm seeking advice regarding a dispute I'm having with my architect. I enlisted their services to create a plan for a dormer loft conversion on my 2-bedroom house. The project was divided into two stages: designing the rooms and roof, which went smoothly, and producing the structural calculation and building regulation plans. This is where the problem began.

The architect decided to use steel instead of wood for the entire project, despite initially saying that the steel only will be used for beams to support the structure because of truss roof. This decision has made it difficult for me to find builders willing to take on the project. I approached few builders asking for quotes and everybody scratching their head saying that wood is the most common way to do it. I relayed this information to the architect, but they insist that steel is the way to go due to the full size dormer. The can change it to wood but it will be extra chargeable.

I was never consulted on the choice of material, and I feel that the design and calculation provided by the architect are not suitable for my needs. My concern is whether I am obligated to pay for this design that no builder wants to undertake. Any advice on how to proceed would be greatly appreciated.

Thank you,
Mario

 

[freddiemercurystwin]

It's tricky to answer on a forum, obviously from what you're saying the architect (are they actually and architect ie ARB registered or what?) didn't listen to your instructions so you should be sticking to your guns and refusing to pay for a redesign, that said there are always two sides to every story.

So it comes down to their appointment and what they were instructed to do, who said what and when and is it in writing etc.

 

[mariohi]

No, they are not an actual architect - structural engineers/designers, not ARB registered. I asked for a standard dormer loft conversion plan and got something nonstandard that builders are not willing to touch.

 

[wessex101]

The steel box sections are usually a proprietary system such as Telebeam. Contact the manufacturer/supplier and they should be able to provide with details of a few contractors who are familiar with the system.
If the existing roof is made up of trusses the steel box section system is probably a good choice.

 

[freddiemercurystwin]

There was a detailed thread on here sometime where they did a (big) trussed roof conversion, I think that was pretty conventional, I'll see if I can find it.

 

[tony1851]

If your house is 2-bed with a truss roof, presumably its a relatively modern terrace- or semi-detached house, right?

Truss roofs are not the easiest to convert, but it can be done. In that case, a dormer loft conversion would probably need four steel beams - one for the ridge, and three for supporting the dormer and floor (unless you use the Telebeam proprietory system noted by Wessex - though likely to be expensive).
In some cases, you can build the dormer front directly off the inner skin and so avoid one steel beam.

The rest of the dormer, ie floor, dormer front and cheeks, and roof is usually done in timber.

Can you post a pic of the plans (with address deleted)? Would be interesting to see how its 'all done in steel'.

 

[mariohi]

It's semi-detached. I included the photo with a marked house in question. I will PM you plans shortly, there is lots of drawings/calculations and I'm not sure what is relevant to your question.

I'm looking for this type of conversion:

 

[freddiemercurystwin]

Wow! Did you get planning permission for that then?

 

[wessex101]

Wow! Did you get planning permission for that then?

Probably permitted development. It certainly is a thing to behold!

 

[mariohi]

It's a permitted development area so just building regs.

 

[wessex101]

It's a permitted development area so just building regs.

I hope you are 100% sure you have complied with all the permitted development criteria or got a lawful development certificate from the council.
Otherwise that could be a very expensive mistake. I'm not sure why anyone would want a loft conversion like that where you can't have proper windows.

 

[freddiemercurystwin]

It's a permitted development area so just building regs.

Ahh for some reason I assumed it was a recent build so would have restricted PD rights.

 

[mariohi]

I got the lawful development certificate from the council. The windows will go on the sides of the dormer. As you can see there are limited options and this seems to be the best way to get extra space.
House was built in 2010.

 

[freddiemercurystwin]

Begs the question if it's PD why didn't you do a dormer on the other side too?

 

[Mister Banks]

Hi everyone,

I'm seeking advice regarding a dispute I'm having with my architect. I enlisted their services to create a plan for a dormer loft conversion on my 2-bedroom house. The project was divided into two stages: designing the rooms and roof, which went smoothly, and producing the structural calculation and building regulation plans. This is where the problem began.

The architect decided to use steel instead of wood for the entire project, despite initially saying that the steel only will be used for beams to support the structure because of truss roof. This decision has made it difficult for me to find builders willing to take on the project. I approached few builders asking for quotes and everybody scratching their head saying that wood is the most common way to do it. I relayed this information to the architect, but they insist that steel is the way to go due to the full size dormer. The can change it to wood but it will be extra chargeable.

I was never consulted on the choice of material, and I feel that the design and calculation provided by the architect are not suitable for my needs. My concern is whether I am obligated to pay for this design that no builder wants to undertake. Any advice on how to proceed would be greatly appreciated.

Thank you,
Mario

Ecotrus.com use steel in loft conversions. There are lots of videos on YouTube showing how they build them.