Garage conversion help and advice required

[Joshwa2k]

I am strongly considering converting my garage into an office and utility/WC but to be honest, whilst I know what I want, I'm not sure where to start.

I have planned out the project on Sketchup here - //www.diynot.com/network/Joshwa2k/albums/24589/92734 and spoken to an architect (indirect family friend) who quoted £1k +VAT to do a site survey, proper drawings and building reg requirements. This immediately caused me concern that the whole project would cost a lot more than expected (I haven't proceeded with this yet). I then had a builder (again Friend of the family) quote for the work itself and they have quoted £5.8k for the building work, £1.6k for plumbing & £1k for electrics (again all +VAT). This doesn't include for things like WC & Basic unit that we will supply).

The total for the whole project is much more than I expected and I am torn because I feel I am not incapable of doing much of the work myself (stud walls, plasterboard, suspended floor etc.) and get Builder/ Electrician/Plumber/Plasterer in as and when required.
However I wouldn't know where to start with regards to the building regs etc. and I feel £1k +VAT is quite a lot given the relatively small project.

The rough scope of work is:
- Support load bearing wall and form opening from Kitchen to new office area, insert lintel and door liner and hang existing 1200mm doors that I will supply. Work will need to be completed by a builder.
- Support garage rear wall and form opening for window, install 915x1200mm uPVC window. Builder to supply window and complete work.
- Brick up existing garage door
- Insulate between existing roof joists and fix two layers of 12mm plasterboard, tape and skim. I could easily do this and then have it skimmed by a plasterer.
- Construct stud-work partition walls to form divide between what will be left of the garage & office and office & utility room. Again I could do this and have it skimmed.
- Prepare existing concrete floor with 2 coats of liquid DPM & lay 50x50mm timers to bring garage floor up to existing kitchen floor level, infill with 50mm Celotex & cover with 18mm plywood. Again, I think I could do this.
- Stud-work, insulate & plasterboard in Utility room as this is currently only a single skin brick wall and will also allow to conceal electrics / plumbing to toilet, washing machine and tumble. I could do this.
- All associated work for skirting, door liners, architraves and supplying and hanging doors which I would have the builder complete.
- Install WC/basin unit which we will supply and associated drainage work. Builder to complete this.

- Drain heating system and move radiator to allow for door opening to be made in kitchen.
- Extend pipework to provide H&C services for toilet, basin and washing machine
- Provide waste pipework/traps for sink and washing machine
- Extend pipework and supply 1 radiator in office area
- Install WC/Basic unit that we are supplying.
- I would have a plumber to all this work as this is not one of my strong points

- Wire and provide power for washing machine, tumble and spare double socket in utility room
- Supply and install LED down-lights for office and utility room
- Supply and install extract fan to utility room
- Supply and install 2x double sockets in office area
- All of this I would have an electrician do for obvious reasons.

Any advice of where to start on this type of project would be most appreciated, I have hundreds of questions in my head but I'll see where the conversation leads initially.

Thanks in advance,
Josh

 

[freddiemercurystwin]

The quote for the Building Regs drawings is way too much, assuming planning permission isn't required, no need for an architect though, employ an architectural technician, expect to pay about half what you were quoted+ local authority fees. That said if you employ a builder to do this then you should make sure he's done a few garage conversations before and if so he shouldn't need any drawings. The quote you have received from builder is about right. If you do it yourself though then it'd be worth paying a few hundred for a set of drawings you can work to, they'll allow you to plan ahead and know what materials you've gotta buy etc. Also you may run into problems with achieving a safe means of escape unless you make that window in the bog a fire escape window.

If you have a google I know there are at least a couple of garage conversion guides on various local authority websites which pretty much dictate how to do achieve building regulations compliance.

 

[Joshwa2k]

Thanks for the advice, gives me some hope it may be achievable one way or another. The one bit of confirmation I did get out of the architect for free was that he definitely didn't feel PP would be required. I will get some additional quotes in.

Also you may run into problems with achieving a safe means of escape unless you make that window in the bog a fire escape window.

I plan on having a door going from the new office into what will be left of the front of the garage (just above right where the wording 'Consumer Unit' is on the drawing. Mainly for taking the bins out etc. and easy access into the garage but do you think this would also satisfy a safe means of escape?

 

[roryfirth]

Hello Josh.

I'm doing something similar at the moment. I have an integral single garage which is 2.5x5m.

I had to apply for Building Control notice but no planning permission was needed. The cost for the notice was £378.

I paid a builder to take out the garage door, remove the entire front brickwork of the garage which included a pelmet above the door and replace with new brick, install an insulated block cavity wall and install the window which I supplied. He also installed a warm roof on the small part of the garage which sticks out. I agreed a £3500 cash deal with him.

I also paid an electrician to replace the old fuse box and wire 3 new sockets and 6 spotlights - This cost £450.

Everything else I am doing with my Father, including:
Raise the floor using 120mm joists, 100mm celotex board.
New ceiling using 2x2 batten and plasterboard - If the garage is below an existing room and you are going over the existing celing you don't need to insulate - If you rip the old ceiling down you do.
Insulate walls using 50mm insulated plasterboard - This is overkill for most of my walls as they are all cavity with 50-70mm insulation. It literally just sticks straight onto the existing brickwork so no studwork needed!

Building Control have been easy to deal with. They came out to check the footings for the new wall were the correct depth but were then happy they wouldn't need to come out again to check the rest of the building work not done by me, I have taken picture along the way though just in case.

As I paid a certified electrician to do the work they are are happy to wait to get the notice from the electrician, again I have sent scanned copies of the certs to them.

They want to come out and check the floor is properly insulated bur were happy with a layer of liquid Bitumen, with 120mm joists and 100mm celotex. As I had most of the materials needed when they visited they said they wouldn't need a further visit until after I has finished.

I am going to use a heat matt under laminate flooring which will be wired into a fused spur.

I reackon it will be around £7k when done and this includes getting the room skimmed and around £500 on tools I didn't have (and a new TV for the room...) This also includes the replacement windows.

The floor was a bit of an arse to get right, and I recommend investing in a laser leveller... I got a cheap £30 of ebay and it helped a lot!

The internals are something anyone with an ounce of savvy can do. I spent a lot of time watching videos on you tube to work out what I did and didn't need to know...

Yours does sound a lot more involved than mine but good luck!