Is it possible/cost effective to insulate a prefab garage to use as a workshop?

teaselMay

See what you mean!

If it's possible to change a few of those roof panels for transparent ones that'd make a big difference to light wouldn't it. I'm jealous of your workshop!

Section62

https://forums.moneysavingexpert.com/discussion/comment/81957991#Comment_81957991

People were still (re)using asbestos cement sheeting in the 1990's (and much later). The garage could be secondhand, or old stock, or re-roofed with older sheeting. It was still (legally) on sale in 1999, and a lot sold after that.

The wall panels usually have a nib and recess on the edges to help weatherproof them. If so, removing the bolts isn't enough to be able to remove a panel, you have to do a fair amount of dismantling to make space to ease the target panel out.

The panels are usually surprisingly heavy - the concrete is dense (which is why they are difficult to drill) and that makes even thin sections heavier than they look.

KBM68

So removing panels is not possible (sad)

My workshop will be fantastic! & warm! I am considering a smaller warm box inside it for sitting down tasks

If I was to replace the roof panels - how could that work with insulation?

teaselMay

This sort of thing affords some insulation https://www.trulypvc.com/products/35mm-clear-polycarbonate-sheets

You could change the wooden doors to french windows or similar for natural light too, there are often sets of double doors going for about £100 on marketplace and local groups. The wooden doors will be an easy thing to change.

Section62

https://forums.moneysavingexpert.com/discussion/comment/81958036#Comment_81958036

No, the panels can usually be removed, just it usually isn't as simple as removing the bolts.

Personally, if I was going to the expense of making the interior insulated and lined, I'd start by replacing the roof. Ideally with something like plastic coated steel with a thick insulation layer underneath it. If the roof is coming off then it is likely to be easier to remove one of the wall panels to put a window in.

If you haven't already, check the planning consent to make sure thare aren't any conditions on using the garage for anything other than parking a vehicle.

KBM68

OK this is starting to sound more than barely competent DIYer

I loved the idea of gluing the insulation on - but replacing doors and roof panels is more than I can imagine, I was already panicking about the ceiling at normal 2.4m

Ok scale back and only do the essentials but dont do anything that I'll have to disassemble if I get cash in the future

KBM68

Are there any damp/condensation issues with gluing insulation to the concrete walls? Am I supposed to leave a cavity?

Plus there needs to be a dpc on the floor I guess

WIAWSNB

https://forums.moneysavingexpert.com/discussion/comment/81958005#Comment_81958005

What's the head height to the horizontal bar?

And could we have some pics of the wall construction, including the top of the wall where it meets the ceiling?

WIAWSNB

https://forums.moneysavingexpert.com/discussion/comment/81958096#Comment_81958096

There shouldn't be, assuming the walls don't leak or are damp.

The floor will surely have a dpc already in it - is it dry and dusty?

Section62

https://forums.moneysavingexpert.com/discussion/comment/81958139#Comment_81958139

It would be a bit unusual to put DPC under a pre-fab garage floor. There would be an expectation the floor would get damp/wet from the vehicles, as well as possibly water getting in through the door or gaps between the wall panels/floor.