Wooden frame extension - is this a thing in the UK?

[MorphDoc]

Hi,

I am thinking about extending over garage and utility room to add en suite bedroom.

The garage has single layer with pillars, but the utility room has double brick (I believe these were built separately!). The garage is about 4.5m in length.

I have not checked the foundation which obviously will change a lot, but I have read somewhere that it is possible to build "lighter" extension over single brick wall with pillars, using timber frame. I cannot find much information about this on the internet, but I was wondering if anyone has any experience of over garage extensions using timber frame?

 

[Notch7]

the big factor will be what the external house walls are

If the house walls are brick, then you are unlikely to get planning consent for an extension in a different material.

if your house is say painted render, then you could consider a timber frame extenion.


In terms of practical consideration, yes it is entirely possible to build a timber frame extension on top of a garage. You will likely require a structural engineers calcs / design to satisfy building control - sometimes a single wall garage needs steel beams like a wall plate around.

as far as construction, it’s just standard timber frame - although detailing for damp and vapour is more complex

 

[^woody^]

The foundation requirement will be the same whether masonry or a frame. A single skin wall is unlikely to be suitable for supporting a second storey of any construction.

You could get planning consent for a well designed frame with different cladding to the main house. For permitted development, the external appearance should be similar to the main building.

The advantage of a frame is potential speed of construction and better thermal insulation for the same wall thickness in masonry. Or less eco-impact if you are concerned. There are more disadvantages compared to masonry.

But the advantages are only fruitful if you have a good designer and experienced frame erectors, not general builders who 'did one of those a few years ago down the road'.

 

[MorphDoc]

Thanks for replies.

House is made from brick.

So the only way to build extension over garage is to...demolish the garage and essentially build 2 storey extension.

Wish I was born earlier so that these would cost peanuts...

 

[23vc]

I was told by building control after exposing the foundation that my single skin garage wall could take a cavity wall 2nd story (decided to demolish it instead tho as it wasn’t quite where I wanted it)
Bloke down the road with the same house was told he couldn’t do the same thing.
Fwiw, there’s an old red brick detached house near me with a very strikingly different first floor timber clad/timber frame extension, so doable from a planning perspective