Home DIY

This might sound obvious, but (properly) check the location of anything that might be under the floorboards, or else this:

I worked out where the pipes were perpendicular to the floorboards, but failed to appreciate that they might do a ninety degree turn. With hindsight, this was a little naive.

I'm not sure, especially since I haven't seen your boards. I'd possibly be tempted to screw down solid and then belt-sand any level differences.

Humans are quite heavy - 6mm will flex a lot.

18mm will create a nice stable floor. Depends on how uneven the floor is, I guess, that said - but I'd be tempted to go for the "do it once" approach.

^^^ ditto check under floorboards, screwed through a water pipe a couple weeks ago doing exactly what your planning on.. it was mental. also cost a fortune to get it fixed.

i did it again about an hour later..... so poor now!

All the above, but also even if you're 100% sure you're not drilling through a pipe, make sure you know where the stopcock is and that it works. When we moved in, every single valve was seized so the only way to turn the water off was at the meter in the street, which is about 30 half turns with an adjustable spanner.

Also, equivalent for electrics

Thanks all. Yeah I'll definitely check (properly) whats under the floor boards and make a good note of it.

Am going to go ply, still need to mull over the ply thickness/door planing/floor unevenness scenario. Will let you know how it goes when I start. Thanks again.

Secure plywood to floor joists not floorboards.

OSB is cheaper than ply and does as good a job unless it's likely to get damp...

also, use screws that aren't long enough to go through the floorboard

Secure plywood to floor joists not floorboards.

^This is good advice, which I forgot.

What if the joists are a hundred years old and very old and bowed?

I destroyed my rotten old shed this evening. It was rank - a lot of the planks, struts and the carpet which had inexplicably been placed across the floor were rotten.

A new shed is on the way.

Is the base which you can see in the last picture going to be enough to build a new shed on? I think getting a concrete base built is going to be a bit too expensive for us.

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i was talking to a loft guy about boarding my loft. we have very bendy rafters that are very old. he said that when you screw into them you have to be quite carful as you can pull them up slightly with the screws. not enough to damage the joist, but enough to crack the plastered ceiling below.

he packed out the gap between bendy joist and board with thin bits of wood, 3mm ply i think. might be worth thinking about for floorboards too. j

my house is edwardian and there's a difference between rafters in the loft/1st floor ceiling and joists in the 1st floor "floor" and ground floor ceiling. e.g. rafters in the loft are approx 4" whereas joists for you to walk on on the 1st floor are approx 8"

That base will be fine.

ah good to know!

#tommmmmmm That base is a water feature waiting to happen, it's no wonder everything was rotten underneath. You need to have the base above the surrounding grounds and make sure that it slopes away from your structure.

So the base should be sloping?

What's the cheapest way of getting a base done?

It may be as simple as putting breeze blocks or slabs on top of what is already there, assuming it is fairly solid and level. That would then raise the shed floor off the ground. Or use pressure treated batons at right angles to the floor supports.

A 9'x7' concrete base is going to cost me £700 but only because I don't have what you have to start with.

I have 8 x 60cm sq flagstones which I was going to pull up anyway from elsewhere in the yard. Should I just space those out evenly on top of the former base?

I was planning on digging down the areas next to the base anyway so that should take it above the surroundings.

The base should be level, the surrounding soil/sod should slope away from it. What #stevo_com said about base materials: my shed has sat on pressure treated 4x4s for the last 20 years or so.

If you want belt and braces go with flags and batons (make sure they are pressure treated, not dipped). But as long as your floor is on a level foundation and not permanently wet you'll be ok. What shed are you going for? (I have been geeking out on sheds recently).

A cheap one, 6ft x 6ft Shire Arran.

If I used batons, would I have to fix them in any way or just lay 'em on down there?

If you can stretch the budget, pressure treated will save you having to replace it sooner and you might even get an ROI from the regular treatments you might have to apply.

If you get 4x4's like WP has and enough of them (5 or 6) then you might be fine just plonking them down. If anything, you could secure them to the floor panel but it unlikely to walk unless in a very exposed windy area.