Garage lining & insulation

George Power Finch · 22 Jan 2021

Hi all,

Will try and keep this short. Recently bought a house and it has a very old double garage (from 1964) which has been used as a bike workshop for a long time and I wish to convert it into a man cave / editing room for my job - so will need lots of sound proofing.

I really do not know where to start, how do I stud wall the walls when there's sectional concrete pillars around the whole thing?

I've removed some floor panels and its quite damp / mouldy under there so can I use SLC over the old flooring to rectify that?

I also need to block up the garage doors internally with a stud wall but there's huge metal hinges on either side of the doors so I'm not sure how to combat that either or how to do it effectively.

The easiest job seems to be the roof which has 100mm joists so I'm guessing some 100mm Rockwool slabs and then plaster boarding it? I'm going to replace the current lights with basic stick on LED ones so they don't need to retract into the ceiling at all.

Any help on there stud walls would be greatly appreciated!

[GALLERY=media, 105920]Garage-9 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105921]Garage-10 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105919]Garage-8 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105918]Garage-7 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105917]Garage-6 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105916]Garage-5 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105915]Garage-4 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105914]Garage-3 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY] [GALLERY=media, 105913]Garage-2 by George Power Finch posted 22 Jan 2021 at 12:21 AM[/GALLERY]

JohnD · 22 Jan 2021

I do not recommend drilling the thin concrete sectional walls. As you can see, this leads to spalling, cracking, and pieces breaking off.

if necessary, you can remove some bolts (one at a time) and replace with (preferably stainless) studding, and you can fasten a bracket under each nut.

it is unusual that you do not seem to have a concrete slab floor. Show us more.

The unsupported span of the roof timbers looks excessive and may not take much weight, e.g. of a workman or thick wet snow and ice. It may need recovering.

George Power Finch · 22 Jan 2021

JohnD said:
I do not recommend drilling the thin concrete sectional walls. As you can see, this leads to spalling, cracking, and pieces breaking off.

if necessary, you can remove some bolts (one at a time) and replace with (preferably stainless) studding, and you can fasten a bracket under each nut.

it is unusual that you do not seem to have a concrete slab floor. Show us more.

The unsupported span of the roof timbers looks excessive and may not take much weight, e.g. of a workman or thick wet snow and ice. It may need recovering.

Thanks for the reply John.

There is a concrete slab underneath the black rubber matts, I did attach a photo (5th one in( but the concrete is somewhat stained from the many years of damp and mould so probably quite difficult to make out.

There isn't a huge budget for this project so I'm not sure on costs for stainless studding.

The weight the roof can take is surprisingly high, there's a mixture of wooden and concrete support beams and there's 3 vertical beams altogether, for reference the whole garage is 5m x 5m.

JohnD · 22 Jan 2021

this sort of thing in M6. Usually cheaper than nuts and bolts. Less than a pound each, if you need a quantity you can beat the price down.
https://www.ebay.co.uk/itm/A2-STAIN...893493&hash=item5434293b9f:g:lyEAAOSwRgJXjxO2

As it is rustproof it will not expand and crack the concrete, and you can use a size smaller than galvanisd as it will not be weakened by corrosion.

you can buy galvanised cheaper for dry conditions. M8 is used a lot by electricians. I used to use it in the garden for fenceposts and sheds, but it rusts and breaks in time. i think mine was 4metre lengths. I had a terrible job drilling it out of concrete fenceposts with cobalt drills, which is why I use stainless now.

if you can cut it to length yourself it is cheaper (hard work)

you will also need nuts and large washers

The carpenters or roofers know about timber sizes and spans. 5m is quite a lot.

BIGbadmarky · 22 Jan 2021

I wouldn't fix to the sectional concrete. Just seems like a world of hurt. I'd think about an independent timber frame wall on the inside. Fix to the floor and the roof members and internally line with something appropriate. Depending on how moist your garage is you might want to avoid plasterboard.
You could stick some mineral fibre batts between the timbers. It would be great acoustically and thermally.

^woody^ · 22 Jan 2021

Independent insulated stud wall. See some of the many garage conversion threads.

George Power Finch · 22 Jan 2021

Gotcha! Will look into this. Any tips on blocking up the garage door internally? I was going to use expanding insulation foam to block up all the gaps between the garage door / wall / floor then stud wall it with some beefy insulation?

Terrywookfit · 22 Jan 2021

Basically you need to build a shed inside of the existing shell. Like a Timber framed house.

^woody^ · 22 Jan 2021

The garage door will get condensation on the back of it, so the design of the timber frame needs allow for this - barrier on the back of the frame to prevent exposure to a humid cavity, and drainage or ventilation of that cavity - so it may not be best to completely seal up around the door.