Concrete sectional garage on paving slabs?

Bluebell1000

We have a concrete sectional garage in pieces, and an area of paving slabs where we'd like to put the garage. Online advice is to put down a concrete base instead, but I was wondering why - what would actually happen if we put up a garage on paving slabs? Would it / could it work on slabs?

Note - we'll be assembling it as a short garage (i.e. not using all the sections) for storage, and not for a car.

ic

My guess is it would sink on the edges over the time, with the flags tipping up or cracking - they, and the foundations beneath them were never intended to take the weight of all that concrete - just some potted plants, garden furniture and people moving around.

EachPenny

Bluebell1000 wrote: »

We have a concrete sectional garage in pieces, and an area of paving slabs where we'd like to put the garage. Online advice is to put down a concrete base instead, but I was wondering why - what would actually happen if we put up a garage on paving slabs? Would it / could it work on slabs?

It depends how thick the slabs are, thin slabs will crack, thicker slabs will tilt unless they are positioned centrally under the concrete panels.

If the panels are placed centrally on the slabs there will be a strip outside the garage which wil collect rain and allow it to run under the walls into your storage area. The way of stopping that is to put a concrete fillet around the outside of the bottom of the panels so the water cannot get in and drains away. If the slabs move at all, then the concrete fillet will crack and fail.

Hence the advice to have a solid concrete base.

A compromise solution could be to put a concrete strip foundation around the walls of the garage/store and then use slabs to cover the area inside. There is no need to have a thick concrete base in the middle if you aren't going to be keeping a car in there.

Bluebell1000

Thanks, useful stuff. Your explanations make much more sense that what I'd found on the internet

If that garage can't be rebuilt we'll get a timber shed, so I am in part reluctant to pay out for a base if it turns out the garage is knackered. My OH is reasonably confident it'll be OK though since we only need 14 out of the 19 sections anyway.

It will be used for a train, but a ride-on garden scale one, which will have a rail running into the garage/shed so the weight will be spread. Not a massive concentrated weight or anything. Slabs are 70mm thick concrete ones, not the decorative garden type.