Garage Conversion - DIY?

benmc

Active Member
Hi All

I currently planning a garage comversion and I am considering doing the work myself rather than getting builders in.

Here are the plans and details.

I can't see any major issues but I would not be sure what order to do things in?

What do people think?

Regards
ben


CONSTRUCTION NOTES
BUILDING REGULATIONS


1.0 - WALL FINISH TO EXTERNAL PERMIETER WALLS

- Kingspan Kooltherm K18 insulated dry-lining board fixed to 25x50mm timber battens set at maximum 600mm centres fixed to brick wall. Skim finish. To provide a maximum U value of 0.28W/m2K
- The wall dry-lining insulation shall be Kingspan Kooltherm K18. Insulated Dry-lining Board comprising a 12.5mm plasterboard facing bonded to 72.5mm thick CFC/HCFC-free rigid phenoic insulation. Manufactured to the highest standards under quality control systems approved to S EN SIO 9001: 2000/ I.S. ISO 9001:2000 by Kingspan insulation Limited and shall be applied in accordance with the instructions issued by them
- Timbers should run vertically and be wide enough to offer a minimum 20mm support to all four edges of the board. Galvanised clout nails, long enough to allow a minimum 25 mm penetration of the timber, should be placed at 150 mm centres and not less than 10 mm from the edges of the board. They should be driven straight with the heads embedded just below the surface of the board. Care should be taken not to overdrive nails. Timbers should be treated where appropriate
- Contractor should check that external walls have DPC. If there is none it is recommended that a liquid DPC be injected.

2.0 - WALL FINISH TO INTERNAL PERIMETER WALLS

- Fermacell 12.5mm fixed to 25x50mm battens fixed to brick wall. Skim finish.
- Refer to Fermacell “The Orange Book” for guide to installation

*3.0 - NEW DIVIDING WALL CONSTRUCTION

- Dividing wall construction,12.5mm Fermacell board to each side, fixed to 150x50mm vertical timber stud at maximum 600mm centres with full fill mineral wool insulation batts in cavity (Rockwool Flexi Batts or similar approved) with vapour control layer.
- To provide min 30mins fire protection and 44db sound insulation
- Refer to Fermacell “The Orange Book” for guide to installation
- All to provide maximum U-Value of 0.23 W/m2K.


4.0 - NEW FLOOR CONSTRUCTION

- Floor construction, install DPM on top of slab with 60mm Celotex laid to achieve 0.25W/m2K
- Vapour control layer to be laid over Celotex and turned up 150mm at room perimeters behind the skirting.
- Chipboard floor finish to be minimum 18mm tongued and grooved floor grade type C4 to BS 5669. Lay chipboard with staggered joints, glued with a woodworking adhesive
- Provide a 10-12mm gap at all perimeters and abutments to allow for expansion
- At all external doorways (for the width of the threshold), a treated timber batten must be used in lieu of the insulation boards
- Use Celotex T-Break TB3000 boards as upstands to fit around floor perimeters to eliminate thermal bridging at screed edges
- Timber hardwood floor finish to clients specification and approval (approx 20mm)
- Total floor build up 100mm to match FFL of adjoining kitchen




* 5.0 - NEW CEILING CONSTRUCTION – INSULATION AT CEILING LEVEL

- Ceiling construction, 12.5mm Fermacell nailed or screwed to 63x200mm grade C16 timber at 400 c/c. Fixed to brick wall with face fixing hangers – 4no hilti HIT-HY injection anchor with HIT-AN/HIT-IG on each support
- Insulation cross layered (between and over ceiling joists) 200mm full fill Rockwool mineral fibre insulation between joists
- 150mm cross battening to joists filled with 150mm Rockwool mineral fibre insulation
- 18mm floor board nailed or screwed to top to provide area for storage
- All to provide maximum U-Value of 0.16 W/m2K
- At eaves use 70mm Rockwool mineral fibre insulation, ensure insulation meets wall insulation
- Ensure use of proprietary cross flow ventilator or ensure 25mm (min) air gap at eaves
- Ensure there are soffit vents, or alternatively drill holes in barge board and cover with insect mesh to provide equivalent of 10mm continuous ventilation gap
 

Attachments

  • HN0120-02 PROPOSED (REV C).pdf
    79.1 KB · Views: 2,302

richjamesw

Standard Member
Hi Ben

Did you do your garage conversion in the end, was it for yourself and did you do it yourself. Im going to be converting mine and this has a similar proposed layout to yours. Is there anything you would recomend from your previous experience with this?
Did you do a building notice or building regs?
 

benmc

Active Member
Hi Ben

Did you do your garage conversion in the end, was it for yourself and did you do it yourself. Im going to be converting mine and this has a similar proposed layout to yours. Is there anything you would recomend from your previous experience with this?
Did you do a building notice or building regs?

I did the whole thing myself in the end. Only got people in to fit new back door, electrics and wood flooring.

Mine was fully under a building notice and signed off by Building Control.

Ben
 

richjamesw

Standard Member
im in the process of doing my drawings and came a bit stuck on the floor constrcution. I was intending on putting down c16 100x50 timber frame to perimeter then at 400c/c but was going to fill bottoms with dried sand to sit insulation (70mm) on top.
was this something you had considered?
how many hours do you think it took you?
 

benmc

Active Member
im in the process of doing my drawings and came a bit stuck on the floor constrcution. I was intending on putting down c16 100x50 timber frame to perimeter then at 400c/c but was going to fill bottoms with dried sand to sit insulation (70mm) on top.
was this something you had considered?
how many hours do you think it took you?


My floor was just 60mm Celotex laid on the floor with a floating chipboard floor on top.

Mine took about 6 months
 

bladster

Active Member
Guys, not sure if it will help but here are the plans that I knocked up and submitted to the planning regs people. The guy did his first visit, didnt even look at the order or plans, just said "what can i tell you..."

Mentioned the front footings (which arent deep enough, Grrr) the insulation above the very front on the garage bit (its integral so insulate it), the floor having a DPM and puttig in insulation and using good joists between the house and garage.

Im still stuck on gettig abuilder to do the fancy brickwork on mine £2.5k current cost! but good to you all. make sure you post losts of pics, insparation to us all.

J
 

Attachments

  • Copy of garage plan.zip
    29.1 KB · Views: 2,324

benmc

Active Member
Some further real world figures.


17/8/06 Joists (28 at £1.59) -44.52
17/8/06 Building Regs Paperwork -240.00
17/8/06 Screwfix Order -154.45
18/8/06 Axminster - Drills -95.95
20/8/06 Costco Membership -29.37
20/8/06 Costco -277.00
20/8/06 Malletts & Squares -22.43
22/8/06 Joists -191.15
22/8/06 Architect Fees -230.00
25/8/06 Moter -2.01
26/8/06 Screws -9.99
26/8/06 Screw refund & Bolster -7.48
26/8/06 Dryzone -77.00
26/8/06 Buildcentre -16.45
29/8/06 Screws -6.28
7/10/06 Dowel -4.58
8/10/06 DPM etc -62.85
10/10/06 Motar -2.68
10/10/06 Sanivite -249.99
12/10/06 Back door -248.47
15/10/06 Flooring + Rope -28.55
21/10/06 Plasterboard -505.50
25/10/06 Fire Door Frame -94.18
27/10/06 Back door + Fitting -500.00
28/10/06 Flooring & Light -39.13
29/10/06 Lights & Kitchen Copboard -115.63
11/11/06 Wallbolts + Nails -19.27
15/11/06 Screwfix - Vapour Barrier -83.90
18/11/06 Knee Pads -15.26
24/11/06 Plasterboard -36.38
6/12/06 Electrician -120.00
6/12/06 Electrician -150.00
11/12/06 -6.99
14/12/06 Lighting Cabel -14.88
16/12/06 Flooring -37.73
16/12/06 Flooring -45.91
17/12/06 -16.68
21/12/06 Plumbing -250.00
31/12/06 Flooring -37.11
6/1/07 PVA Gule -5.99
20/1/07 Tinber Battens -10.19
28/1/07 ToolStation Order -46.38
29/1/07 Plasterboard -78.82
1/2/07 Insulation + Tinber Battens -69.36
2/2/07 Tinber Battens -42.45
2/2/07 Timber Battens -10.19
5/2/07 AirCon -1,000.00
15/2/07 Door Handle -21.18
15/2/07 Screwfix - Door Stuff -55.89
16/2/07 Screwfix Refund 4.00
17/2/07 Fire Door -49.39
17/2/07 Carpenter - Fire Door Fitting -90.00
18/2/07 Door Handle Refund 21.18
18/2/07 Door Handle -15.19
22/2/07 Screwfix Stuff -33.88
25/2/07 -28.17
26/2/07 Air Con -266.54
3/3/07 -9.48
6/3/07 -32.14
12/3/07 Plasterer -200.00
14/3/07 Plasterer -250.00
14/3/07 Plasterer -120.00
16/3/07 Electric Stuff -9.33
29/3/07 Electrician -270.00
30/3/07 Flooring Deposit -440.62
5/4/07 More Paint -8.54
7/4/07 Laura Ashley Paint -32.40
7/4/07 Layra Ashley Curtains -93.60
7/4/07 Masking Tape -3.79
10/4/07 Cat5 Stuff -27.04
13/4/07 -65.00
3/5/07 2nd Flooring Payment -881.24
6/5/07 Paint Refund 16.20
7/5/07 Paint Refund 12.00
8/5/07 Last Flooring Payment -440.62
18/8/07 Plasterboard -7.98
Total 16/12/00 - 2/2/09 -8,751.77
Total Inflows 53.38
Total Outflows -8,805.15
Net Total - £8,751.7 7

Attached is out actual spend. Note this included the following

Nice Oak Flooring - Fitted
Split Air Con - Fitted
About £750 of tools I needed
Electrician

Hope this helps
 

Attachments

  • Garage Conversion.pdf
    31.2 KB · Views: 1,926

richjamesw

Standard Member
Guys, not sure if it will help but here are the plans that I knocked up and submitted to the planning regs people. The guy did his first visit, didnt even look at the order or plans, just said "what can i tell you..."

Mentioned the front footings (which arent deep enough, Grrr) the insulation above the very front on the garage bit (its integral so insulate it), the floor having a DPM and puttig in insulation and using good joists between the house and garage.

Im still stuck on gettig abuilder to do the fancy brickwork on mine £2.5k current cost! but good to you all. make sure you post losts of pics, insparation to us all.

J

This is the sort of thing im on with now a spreadsheet as well as producing drawings for building regs, doesn't look as if any insulation was put in the walls on your info. Was it required by building regs?
 

bladster

Active Member
Hi Rich

I have a double garage with a cavity type wall between the two garages, of which most of it I have already filled with insulation.

However, yes did say cavity insulation will be needed for the front new wall and a little bit of the side that isnt internal.

I had some from wickes which is probably listed on the spec i uploaded, else the link is

http://www.wickes.co.uk/Cavity-Insulation/Cavity-Wall-Insulation/invt/161208

I showed it to the guy and he seemed happy with that. I just kept going on about how I wanted to have cheap heating bills and best to do it right and he seemed relativly relaxed abotu it all.

I would suggest for building regs, getting the costs down to, keep everything to a minimum (I had 2 cost lists) one for the regs, one actual planned spend. e.g. no extra glue for the bords, just screws etc.

good luck and keep us posted
 

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