Insulation of concrete block shed for external larder

[peejay]

We're all set for completion on new house next week and as expected we're excited AF. The new house is a world apart from our current place but one thing it's lacking today is a decent location for storing pepper-quantities of food, i.e. no real larder type space.

Once we've lived in it a bit there's lots of potential for extension etc. (which will definitely include a larder type storage capability) but in the meantime along with the garage there's a concrete-block built shed that, from my brief viewings, has potential to be put into service (there's also a very good sized garage as well for non-perishables such as bog roll etc.

It's safe to assume that the shed is single skin & has a basic roof - from memory it's perhaps 10' x 6' or so.

I'm investigating whether there are any sensible insulation options that would ideally serve to keep the building at a reasonably constant temperature should it be suitably insulated but I'm aware that if not done correctly then condensation etc. could potentially become an issue.

Does anyone have any experience, or links to resources where people have done something similar?

I'd ask on the building/diy forums but as soon as I say it's for food storage I'm pretty certain the conversation will go off the rails so trying to look amongst prepped-orientated resources for options/experiences.

Preference is to do it well rather than do it cheaply as I'm well aware that the two are often mutually exclusive...

Am I insane or is it feasible?

[Yorkshire Andy]

Depends how much you want to chuck at it...

A modern composite door (basically fiberglass and PIR foam)


https://en.m.wikipedia.org/wiki/Polyisocyanurate

Then walls

Check pointing and gutters and fall pipes to keep rain off the walls

A good cost of Thompson water seal won't harm


Roof depending on type glass fiber or PIR sheets (leave a gap between timbers and insulation to let the roof breath ideally a mvp membrane between tiles / slate / felt and the roof but nothing to stop you stapling it to the underside...

As for the walls you can get pir backed plasterboard...

Or PIR outside and render


Next step is the floor stop water coming up if it's not got a dpc installed DPM and a decent floor screed should do for a lightly trafficked area Dpm lapped up the wall a bit


Now for the Biggie ventilation put a low level vent on the shaded / north aspect

And a high level on the east side. Furthest from the low vent .


Reasoning

Obviously airflow will stop damp

but on a warm day heat will rise and escape by the top vent drawing in cool air from the shaded side


Obviously make it vermin proof as you go metal / aluminium vents are harder to chew through ect

[peejay]

Some great pointers there, thanks! Will look into PIR boards I think but will have to wait until moving in to get accurate sizing/costing.

[Yorkshire Andy]

You can often get seconds cheaper ask at your local builders merchants...

I got enough for my shed roof from work as they ripped an old building down so you might be able to scrounge some

Cheaper option would be a polythene sheet tacked to the wall 2"framing then rockwool cavity batts then board over either plasterboard / hardboard / ply / uPVC cladding

[grenfell]

Keep an eye on builders skips too. Granted i used to work on building sites but i collected enough to insulate my roof and most of the ground floor , all without costing me a penny.