Cost Effective Garage Build?

[Hudson1984]

Hi all,

we've recently converted our garage into a pantry and utility room which sees me without a garage... this needs fixing

at the side of our house we have a 3.9m passage, which is used as driveway space, it leads directly into the garden. I intend to build the garage on here, attached to the house as a flat roof/or lean to.

I've looked at sectional garages and i'd be looking at around £9000 fitted (base would be extra so another £1500 odd) and if I wanted cladding to make it look nice it'll be another £2640. I'd also then want to insulate and line it. So we're getting on toward £15,000 all in once I've added the doors I want

If I build it with a builder, i'm looking north of £20,000

I really don't want to spend all that. So many other household jobs I want to tick off the list so I'm keen to find a happy middle ground.

the garage would be 6m x 3m

I was wondering if I'd do better to build a dwarf wall, and build a timber structure on top of that? that's something I could likely do myself, I built my shed attached to the other side of the house and that wasn't so bad - the worst bit being the base but if I opt for concrete with brick as my base I'm then only building a frame

Now the garage isn't going to be used as a garage really, the front 2m would be partitioned off, to be used for a gym, the rear 4m x 3m would be used as a pub. So my main aim is a warm comfortable space rather than an expensive garage for a car that'll never be in there.

That being said, at some point we'll likely want to move, so I want to be able to say it's a garage with my head held high rather than it's some half arsed shed that'll fall down in any gust if wind!

So my query is:

would the DPM go on the dwarf wall, and then I merely attach my wooden frame on top of the next row(s) of bricks?
would the wall need to be double skinned?
Assuming I build my frame, do I then cover the external side of that with a breather membrane to then clad over - I will then insulate between the frame and line internally. So do I need a vapour barrier too?
I want to get an insulated side hindged door for the front and double glazed personnel door on the rear - how easy are these to fit on a wooden frame?
I will likely clad the whole thing in composite planks (so I don't need to re-treat) is this a simple enough DIY job?

cheers all, quite excited about this plan, just need to make it work

 

[mikeey84]

I think one issue you will face is building too close to the boundary with flammable materials.

 

[RonnyRaygun]

I think one issue you will face is building too close to the boundary with flammable materials.

OK as long as the timber frame has a cladding that is rated for 30 mins fire protection. I did this with my own timber frame extension and used renderboard and thin coat render on it.

would the DPM go on the dwarf wall, and then I merely attach my wooden frame on top of the next row(s) of bricks?

DPC on top of wall at FFL. Lap DPM in.

would the wall need to be double skinned?

No

Assuming I build my frame, do I then cover the external side of that with a breather membrane to then clad over - I will then insulate between the frame and line internally. So do I need a vapour barrier too?

Usually:
Plasterboard
Vapour barrier
Insulated timber frame
Ply or OSB sheathing
Breather membrane
Battens
Renderboard and render giving 30 mins fire protection

 

[^woody^]

OK as long as the timber frame has a cladding that is rated for 30 mins fire protection. I did this with my own timber frame extension and used renderboard and thin coat render on it.

You have a [ventilated?] cavity. How did you protect the frame from fire?

 

[RonnyRaygun]

You have a [ventilated?] cavity. How did you protect the frame from fire?

I didn't. It was passed by BC in the full plans application. Although, admittedly, the same thought crossed my mind as I was typing the reply...not before though

 

[^woody^]

Strictly, the frame needs to be lined with a fire resistant board, then the battens, then the cladding. And intumescent perimeter seal around the boards

 

[Notch7]

Hi all,

we've recently converted our garage into a pantry and utility room which sees me without a garage... this needs fixing

at the side of our house we have a 3.9m passage, which is used as driveway space, it leads directly into the garden. I intend to build the garage on here, attached to the house as a flat roof/or lean to.

I've looked at sectional garages and i'd be looking at around £9000 fitted (base would be extra so another £1500 odd) and if I wanted cladding to make it look nice it'll be another £2640. I'd also then want to insulate and line it. So we're getting on toward £15,000 all in once I've added the doors I want

If I build it with a builder, i'm looking north of £20,000

I really don't want to spend all that. So many other household jobs I want to tick off the list so I'm keen to find a happy middle ground.

the garage would be 6m x 3m

I was wondering if I'd do better to build a dwarf wall, and build a timber structure on top of that? that's something I could likely do myself, I built my shed attached to the other side of the house and that wasn't so bad - the worst bit being the base but if I opt for concrete with brick as my base I'm then only building a frame

Now the garage isn't going to be used as a garage really, the front 2m would be partitioned off, to be used for a gym, the rear 4m x 3m would be used as a pub. So my main aim is a warm comfortable space rather than an expensive garage for a car that'll never be in there.

That being said, at some point we'll likely want to move, so I want to be able to say it's a garage with my head held high rather than it's some half arsed shed that'll fall down in any gust if wind!

So my query is:

would the DPM go on the dwarf wall, and then I merely attach my wooden frame on top of the next row(s) of bricks?
would the wall need to be double skinned?
Assuming I build my frame, do I then cover the external side of that with a breather membrane to then clad over - I will then insulate between the frame and line internally. So do I need a vapour barrier too?
I want to get an insulated side hindged door for the front and double glazed personnel door on the rear - how easy are these to fit on a wooden frame?
I will likely clad the whole thing in composite planks (so I don't need to re-treat) is this a simple enough DIY job?

cheers all, quite excited about this plan, just need to make it work

It’s all very doable for a competent DIYer.

your greatest challenge is detailing it correctly to avoid issues with: damp, rain leaks, interstitial condensation, thermal bridging.

I’m not sure on planning, I guess as its attached to the house it will be class A not class E. In which case I imagine permitted development rules for an extension apply.

Since it’s not accessible to the house nor habitable, I guess building regs won’t apply. Although not sure how part B, fire safety will apply if it’s closer than 1 metre to boundary.




by the way, you could use rendaboard on the sides facing the boundary and eternit type cladding on the front and back.