Building a garden room

[Nikita Norman]

I'm looking into building a garden room against my house out of mostly reclaimed materials, some of which I'll already have here - I've got a 50mm thick conservatory roof in the garage that's the size I want (approx 4x4m) and I'll have my old double glazing to use for the front and side walls too. End wall would be solid.

I'm wanting to build it on the side of the house and get french doors installed for access. So it's turning into more of a conservatory, really...

Anyhoo, my plan is to build a sturdy wooden frame and a part wall around the base, as I won't have enough windows to do full walls.

I'm just after advice on how best to join everything together, and how to build that part wall for best insulation. I do not expect a warm room! But "not as cold as outside" will do. I should have the joining pieces for the roof in the garage with the panels but I think I'll probably have to replace those as it's been in there for a number of years now.

Any other advice welcome too! It'll be under the maximums for planning permission and won't cause any issues for my neighbours, because they've got a massive extension on their side of the fence in the same place which is bigger than my room will be.

Budget flooring suggestions also welcome please! I'm planning on doing concrete footings for the support beams because the solid here is very sandy, although the area does have a fine gravel base under the weeds from a patio that I moved when I first moved in.

 

[noseall]

I'm looking into building a garden room against my house out of mostly reclaimed materials, some of which I'll already have here

I have found that trying to build anything to match an existing roof or footprint or window size or whatever, is infinitely more difficult that starting from scratch. You will need the patience of a saint.

 

[23vc]

I appreciate you want to re-use the roof, but this really won’t give you much improvement on the outside temp whether in summer or winter and will really affect how much time you’ll want to spend in there. For hundreds rather than thousands (potentially…) you could build a decent flat warm insulated roof.

 

[Notch7]

I'm looking into building a garden room against my house out of mostly reclaimed materials, some of which I'll already have here - I've got a 50mm thick conservatory roof in the garage that's the size I want (approx 4x4m) and I'll have my old double glazing to use for the front and side walls too. End wall would be solid.

I'm wanting to build it on the side of the house and get french doors installed for access. So it's turning into more of a conservatory, really...

Anyhoo, my plan is to build a sturdy wooden frame and a part wall around the base, as I won't have enough windows to do full walls.

I'm just after advice on how best to join everything together, and how to build that part wall for best insulation. I do not expect a warm room! But "not as cold as outside" will do. I should have the joining pieces for the roof in the garage with the panels but I think I'll probably have to replace those as it's been in there for a number of years now.

Any other advice welcome too! It'll be under the maximums for planning permission and won't cause any issues for my neighbours, because they've got a massive extension on their side of the fence in the same place which is bigger than my room will be.

Budget flooring suggestions also welcome please! I'm planning on doing concrete footings for the support beams because the solid here is very sandy, although the area does have a fine gravel base under the weeds from a patio that I moved when I first moved in.

So basically you need brickwork up to DPC, then timber frame above.

Just set out your timber frame to allow for your windows and doors - making the openings 10mm bigger.

You need a headplate to go around above the windows which will be substantial enough to take the roof load.

If it was me I’d make a flat roof and not bother with the conservatory 50mm poly.

If you really want a to use the poly you will need to know how to create a pitched roof - unless you are an experienced joiner / carpenter you will come across plenty of problems.

I spent many years designing and building timber conservatory roofs they are not easy.

 

[Nikita Norman]

Thanks guys.

The poly is a flat roof, I got them when they were being replaced with a pitched solid. I'm wanting to maximise light with reusing them if I can.

But, an alternative option would be corrugated tin - I've got some 4m sheets that were the original roof from other houses like mine that are still council owned. More than enough to do this. That would then give me the option to insulate.

How much difference would there be in light levels doing that instead, do we think? The conservatory with the now solid roof is still very light but it's also got taller windows than mine will have, and 3 sides of them to my two.

 

[23vc]

Deffo don’t use corrugated stuff. Poly is slightly better, but a proper roof is miles better and makes the difference between it being a habitable space or not

 

[Nikita Norman]

It's coming down to cost, ultimately. I've got a limited bit of money coming and I'll already have to spend a chunk on my double glazing which is about 10 years past needing doing!

 

[EddyHeavenly]

I did something similar a few months back and found that foundation depth made a big difference with insulation. I used concrete piles and a suspended frame, which kept damp at bay and helped with air flow under the floor.

Garden rooms really benefit from proper airflow, especially if you're planning to use them year-round. I also used this guide from quickgarden, which laid out the structural bits clearly.