Blocking off a garage door

[MyNameIsUrl]

I’m helping a friend convert his garage to a craft/sewing workroom, and am starting by blocking off the garage door with a false wall. Any comments appreciated.

The garage is unusual in that it is integral in a terrace, so it has rooms on both sides and on top, so heating and insulation will not be an issue.

I’m proposing to use timber studding (eg Wickes 38x63) to construct a wall 100mm from the door, and clad it in 9mm ply.

I’ll seal round the metal door with sealant or expanding foam, depending on the gap, and use loft insulation between the door and the new wall 100mm thick.

Maybe I’ll use a polythene sheet hung over the inside of the door to be sure no moisture gets through.

Anybody have any experience of this or any views? Thanks.

[pochisoldi]

I’m helping a friend convert his garage to a craft/sewing workroom, and am starting by blocking off the garage door with a false wall. Any comments appreciated.

The garage is unusual in that it is integral in a terrace, so it has rooms on both sides and on top, so heating and insulation will not be an issue.

I’m proposing to use timber studding (eg Wickes 38x63) to construct a wall 100mm from the door, and clad it in 9mm ply.

I’ll seal round the metal door with sealant or expanding foam, depending on the gap, and use loft insulation between the door and the new wall 100mm thick.

Maybe I’ll use a polythene sheet hung over the inside of the door to be sure no moisture gets through.

Anybody have any experience of this or any views? Thanks.

Heating and insulation are an issue - you are converting a garage into an occupied space. The wall behind the door what is known as a "thermal element".

I would suggest looking at Part L of the building regs and taking steps to ensure compliance now, will save money twice over - once when you come to heat the space, and again when your friend has to rip out a desirable feature when it comes to sale time.

As I understand it, you need to look at the sum of the thermal resistance (thermal conductivity) values and make sure that the resistance exceeds (or the conductivity is less than) the specified figure.

You also need to consider that this room could end up being the coldest part of the house - that cold poorly insulated stud wall will attract moisture from the house and may suffer from condensation.

I would also ensure that the fire resistance of the garage isn't allowed to be compromised (e.g. internal fire doors into the house, and compartmentalisation), so that it can be easily turned back into a garage in the future. (e.g. somewhere to park+charge an electric vehicle).

Part L is here: https://www.gov.uk/government/publicati ... document-l

[pochisoldi]

I’ll seal round the metal door with sealant or expanding foam, depending on the gap, and use loft insulation between the door and the new wall 100mm thick.

I missed that bit.

Treat the new wall and the metal door as a cavity wall - the metal door is the weather proof (but almost certainly not 100% waterproof) exterior skin, and the new wall as the inner skin with a ventilated gap in between to allow moisture to disperse. This may mean leaving the top of the door unsealed, and making suitable provision at the bottom to stop surface water from outside coming in, whilst allowing air to flow when the water's gone away.

[DrFfybes]

Is this a temporary conversion for hobby use or a permanent change? If the former then hake sure it is easy to return to a garage if that is what will be required.

If permanent then there are a whole load of other things to consider here, as well as making sure it conforms to building regs if he wants to sell the place later with it classed as a room.

What is the floor made of, is it insulated, will a suspended floor be fitted, how will the underfloor be ventilated and insulated.
Does the door lead to the kitchen, is there a means of escape from this room?
Will there be sufficient ventilation to the new room, will it need a new window?
Will it meet Part L as already mentioned for insulation.

A good start is Paul Hymer's book "Home Conversions". It is a bit out of date now but can be picked up for peanuts on Amazon.

Paul

[todthedog]

Galvanised metal stud and track is worth considering. Easy to fit and won't rot.

[MyNameIsUrl]

Is this a temporary conversion for hobby use or a permanent change? If the former then hake sure it is easy to return to a garage if that is what will be required.

If permanent then there are a whole load of other things to consider here, as well as making sure it conforms to building regs if he wants to sell the place later with it classed as a room.

What is the floor made of, is it insulated, will a suspended floor be fitted, how will the underfloor be ventilated and insulated.
Does the door lead to the kitchen, is there a means of escape from this room?
Will there be sufficient ventilation to the new room, will it need a new window?
Will it meet Part L as already mentioned for insulation.

A good start is Paul Hymer's book "Home Conversions". It is a bit out of date now but can be picked up for peanuts on Amazon.

I'd say semi-permanent, in that I'd expect it to be like that for years but could be converted back if required. A bit unlikely though, as it's too small for a modern car.

It's been used as a crafts/sewing/workshop for many years, but the owners want to do it up a bit especially as it gets a bit cold and draughty in winter. The idea is to make a hobby workshop which is a bit more comfortable, not to make a habitable room. Fire door and any necessary fireproofing of the ceiling are all in place as it was built as a garage.

The floor is concrete, with some laminate, which will be upgraded. There's a smoke detector already. No window, but an extractor fan may be installed. The fire door leads to the hallway of the house.