Plasterboarding single skin detached garage

[dsme94]

Hi,

I'm due to get the keys to a property next week which has a detached garage. I intend to use the garage to store my Mclaren 570s, and would like to plasterboard the walls to make it a nice place to be rather than have the exposed breezeblock.

Let's start of with a picture of what's here already:





Method of madness:

2x1 inch treated timber battens screwed to the breezeblock with screws ( https://www.wickes.co.uk/Wickes-Treated-Sawn-Timbe...)
Pl
Knauf moisture resistance plasterboard on top ( https://www.wickes.co.uk/Knauf-Moisture-Panel-Tape...)

No insulation in between.

Will this be adequate to prevent any mold and dampness? I didn't have any intentions to insulate, but happy to be convinced otherwise as the garage is quite a good space.

Will be using a diesel-fueled space heater to take the nip away when doing little DIY jobs in there.

[Mr Squarekins]

How about Tyvek vapour barrier behind the plaster board? Reduced chance of moisture, no real downside.

[wolfracesonic]

Use 18mm ply instead? Far better able to stand up to the rigours of garage life than plasterboard, makes hanging things from the walls far easier, cover the joints with stripwood for a ‘panelled look. More spendy than plasterboard but not if you’re having the latter skimmed by a plasterer.

[Skyedriver]

OSB

[s p a c e m a n]

Cement board?

[Correvor]

I've been doing similar but am insulating and not fitting directly to the wall but have different needs.

If your walls are like mine, you'll need shims to fix the battens so they're plumb. I'd use DPC on wall side of the batten and use a vapour barrier before fixing the plasterboard or whatever else you use.

[fourstardan]

dsme94 said:

Hi,

I'm due to get the keys to a property next week which has a detached garage. I intend to use the garage to store my Mclaren 570s, and would like to plasterboard the walls to make it a nice place to be rather than have the exposed breezeblock.

Let's start of with a picture of what's here already:





Method of madness:

2x1 inch treated timber battens screwed to the breezeblock with screws ( https://www.wickes.co.uk/Wickes-Treated-Sawn-Timbe...)
Pl
Knauf moisture resistance plasterboard on top ( https://www.wickes.co.uk/Knauf-Moisture-Panel-Tape...)

No insulation in between.

Will this be adequate to prevent any mold and dampness? I didn't have any intentions to insulate, but happy to be convinced otherwise as the garage is quite a good space.

Will be using a diesel-fueled space heater to take the nip away when doing little DIY jobs in there.

If anything mclaren man I'd be plaster boarding the ceiling so you don't end up with no clear coat!

[KTMsm]

Is the outside rendered ?

I presume you're having it skimmed as well?

If yes to both then I'd dab the boards on and I can't see why you would need moisture resistant unless it's a particularly exposed location

[Frankychops]

is that a metal door? if so, stick stuff on the inside of that. that's like a reverse radiator.

I'd just paint the wallls and board the cealing, putting insulation where its missing.

[dsme94]

Mr Squarekins said:

How about Tyvek vapour barrier behind the plaster board? Reduced chance of moisture, no real downside.

Will do, belts and braces wont hurt!

wolfracesonic said:

Use 18mm ply instead? Far better able to stand up to the rigours of garage life than plasterboard, makes hanging things from the walls far easier, cover the joints with stripwood for a ‘panelled look. More spendy than plasterboard but not if you’re having the latter skimmed by a plasterer.

I don’t like the finish of plywood, would rather plasterboard it.

KTMsm said:

Is the outside rendered ?

I presume you're having it skimmed as well?

If yes to both then I'd dab the boards on and I can't see why you would need moisture resistant unless it's a particularly exposed location

Yes, it’s rendered, roughcast (pebbledash?)

If rendered, does this mean we don’t need moisture resistant plasterboard? That will save a considerable chunk! I wont be plastering inside, only filling the screw holes and joints then painting straight onto the plasterboard with some form of washable emulsion.

Frankychops said:

is that a metal door? if so, stick stuff on the inside of that. that's like a reverse radiator.

I'd just paint the wallls and board the cealing, putting insulation where its missing.

It is a metal door, it’s also to be replaced for an electric roller door from Hormann once the opening has been widened.

I definitely want a nice smooth finish inside so will definitely be plasterboarding the walls. Te ceiling will be plasterboarded as well with blown wool put in between the ceiling joists.

[Panamax]

This sounds nuts to me - garages need ventilation.

Is there heating in the garage? If not, what's the point of insulation? It'll just make the lack of ventilation problem worse.

[dsme94]

Panamax said:

This sounds nuts to me - garages need ventilation.

Is there heating in the garage? If not, what's the point of insulation? It'll just make the lack of ventilation problem worse.

Well this is why I asked…

The insulation is already in the roof as pictured, I was not intending to add anymore.

There is no heating in the garage, the only heating I will be having is the space heater as per the original post.

[DonkeyApple]

I'd certainly finish insulating the roof and then plasterboard that. As for the walls, plaster is going to give the nicest finish. Dot and dab is probably going to end up almost 2cm thick but for a single skin I think I'd want a moisture barrier at which point I'd probably just use a thin insulated plasterboard glued with foam. It'll give the vapour barrier and a bit of insulation to help keep the temp changes in the garage in a slightly narrower range which is no bad thing for particularly hot or cold spells.

[ClaphamGT3]

I would use a vapour barrier but, as others have said, the more you insulate, the more you need to think about trickle ventilation to keep air movement and, possibly heating.

Make sure the door that you are installing is insulated and check whether your floor slab is insulated. If not and you don't have adequate ventilation, you will have a permanently clammy floor

[Equus]

There seems to be some confusion over vapour barriers.

TL:DR version: you don't want one. You want strips of DPC behind each batten.



Full explanation:

A vapour barrier is a continuous membrane capable of resisting (guess what?) the passage of water vapour (ie. the water held in a gaseous state in air). It is there to stop moisture (water vapour) from inside the building finding its way outwards into the structure (where it can condense to liquid water in the middle of the structure - called 'interstitial condensation') - causing harm.

Beyond that, Tyvek Airguard is an expensive 'intelligent' vapour barrier, offering variable vapour resistance according to prevailing conditions, allowing a certain amount of moisture to breath out when relative humidities are low (hence the water vapour filtering out can easily evaporate off toward the outside), but 'closing up' and giving a very high vapour resistance when RH is high. Clever, but utterly unnecessary in this case.

Very little water vapour is generated in a garage*, so you're not worried about that. Single skin masonry is not good at resisting the passage of liquid water, though, so what you're trying to achieve is to prevent the transmission of any moisture that finds its way into the masonry to the battens or plasterboard, neither of which materials take kindly to being damp. In other words you're trying to stop liquid moisture (rain; not water vapour) from outside the building from finding its way inwards to the battens and plasterboard.

You do not want or need a 'vapour barrier' in this situation.

You do not even want** or need a damp proof membrane (DPM), which is what other posters think they are suggesting, but using the wrong terminology for.

You want strips of DPC (damp proof course - the difference being that it is an isolated strip, not a continuous membrane) sandwiched between the inner face of the blockwork and the individual battens.

Theoretically, render should stop almost all rain penetrating into the masonry, but in practice it is seldom perfect, so I'd use strips of DPM regardless.


* Although a diesel-fueled heater will add some, so if you're planning one of those, I'd use it in moderation. Personally, for something as valuable/cherished as a McLaren I'd use thermostatically controlled oil-filled panel heaters as background heating, with ceiling-mounted infra-red heaters for when you're working in there.

** because it is more likely to trap penetrating moisture in a limited location, causing harm, rather than allowing it to disperse more more widely and safely.

[megaphone]

What is above the garage?

[fourstardan]

megaphone said:

What is above the garage?

The butler who gets OP's mclaren out of one's future dot and dabbed garage.

[57Ford]

megaphone said:

What is above the garage?

Only sky from the sound of it.

[roadie]

You could always try slapping some masonry paint on the walls to see if you are happy with the finish that paint gives before going for something more involved?

[Equus]

57Ford said:

megaphone said:

What is above the garage?

Only sky from the sound of it.

No, that's a fair question: photo shows insulation between the joists and a chipboard deck, which since there'e no air gap above the insulation hopefully means that there's a room above, and the insulation is there to prevent loss of heat downwards?