Summerhouse is about 16ft x 8ft, basic construction and on a concrete base. Looks a bit like this (albeit wider and with single glazed windows as opposed to double):

Roof needs replacing too and am already favouring sedum, so methinks some serious reinforcement is in order to support IRO 120kg/m2!

Is it “just” a case of adding double glazing (inc doors), insulating and plastering the walls, then warming up the floor?

Due to the space we’re looking at it being part office and part chillout zone.

Ta

If it’s over 30m² it’ll need Building Regs, that’s the boring bit….

Don’t put a toilet or cooking facilities in there either to stay on the right side of the law.

Sedum roofs are heavy, I wouldn’t bother, what’s the point, really? By the time you reinforce that enough to take the weight you may as well rip it down and start again. Stick with a lightweight roof covering, or you will need braces at eaves level, which will dramatically reduce the ceiling height and feeling of space you get from the open span in these buildings.

Well it won’t be over over 30m2 so that’s a start.

Won’t be adding any services other than leccy.

Sedum can also be expensive but I’ve seen a couple and really like them. Not convinced 100% but enough to be interested. Either way, I want to proof the walls and flooring to make it comfortable all year round. Hence wondering if insulating a generic timber build can actually work.

Ta

It might not be 100% technically correct, but if you insulate between the studs/rafters with kingspan, put in a polythene vapour barrier, then plasterboard & skim, I can’t see why you wouldn’t be able to use it all year round.

I’m guessing 3×2 or 4×2 studs? if so 75mm between and 25mm continuous over the face would make it pretty warm. same goes for roof, but would go for 100mm between and 25mm under rafters continuous, heat rises.

Floor – domestic standard is 75mm, would advise 100mm though.

if you also double glaze it it should be pretty warm all year with minimal heating.

Roof: http://www.extrarooms.co.uk/garden-office-blog/posts/2013/january/08/sedum-roofing-for-garden-offices/

We use ours all year.

The walls are 44mm thick so we did nothing to those.

The floor we have put down some laminate wood flooring above the standard floor with a nice felt backed insulation layer. We have a large rug down in winter.

The roof we boxed in the standard rafters with some tongue & groove wood and put insulation in between.

We put thicker glass in the windows and door but not double glazed. We then have curtains to keep the cold out at night.

Ours heats up and stays warm with an oil filled radiator at sub zero temperatures very easily.

we use our cabin year round. 45mm walls, double glazed, 50mm kingspan on top of the sarking boards, felt then shingles.
Floor is concrete base, 40mm kingspan, floorboards then 10mm laminate.

Super toasty with just a small leccy heater.

Excellent, just the sort of ideas I was looking for.

Thumbs up y’all 🙂

You would need building regs to turn it into a habitable room whatever the size. What you are describing won’t count as habitable so you are fine there. The power will need sign off, though. You can either get an electrician in who can self certify or diy it if you are competent and get building control to sign it off.

Does this thread indicate a relationship hitting rocky times or someone’s in law coming to stay permanently? 😀

diy it if you are competent and get building control to sign it off.

can you still DIY elec’s ? I thought you had to be an electrical corgi these days ?

speak with your local building control. Unlikely they will want any involvement but best speak with them as opposed to us lot spouting ideas.

I had to go for warrant and planning due to a pain in the arse neighbour and the fact that the laws in Scotland were strict (up until last year(. Now no building control or planning would be necessary for my build, 4.5x4m + power.

Re leccy, a mate is a sparky so that’s covered.

I’m pretty sure there’s no need for BC to get involved as the space isn’t for formal habitation etc. Will double check anyway.

No need for Building Regs. involvement, as stated, it’s under 30m²m. And not habitable (were it habitable, the 30m² rule wouldn’t apply anyway).

On the electrics front, use a Part P electrician, it is the easiest way.

You can still DIY electrics, far more than people realise, but anything outside the main dwelling or in a ‘special location’ (kitchen/bathroom) is covered by Part P.

You can extend & modify existing circuits (provided they aren’t in special locations, as above), without instigating Part P, and most local authorities accept applications for electrical works if you don’t want to use a Part P registered electrician. We request a wiring diagram, inspect 1st fix visually, and get an electrician in to test the circuits on completion. Costs about £200, but there is a limit on the no. of circuits.

Core, I stand corrected, never knew that, cheers

It sounds obvious but you need to seal up all the leaks – round doors and windows mainly. No point insulating a collander!