Getting level foundations

Aug 17, 2005 18 Replies

I am moving a large shed (32' long, 12' wide and 8'high) from one part of a site to another (it is sectional!). Currently the shed is on a concrete slab and sits up on concrete blocks.



At the new location I do not want a lay a slab, but I will be putting down a concrete foundation "ring" on which to lay the concrete blocks.



Very simply, how do I ensure that the concrete foundation is level front/rear and side/side over such a large area?



I can theoretically use a large spirit level and bash wooden stakes into a certain height, but at the end of the day, even a slight mis read over a total "ring" of 88' of foundations could lead to quite a height difference!



Are there any better ways or is it a spirit level, being very careful and possibly an iterative process?



Cheers



Peter



Hi Peter

#>I am moving a large shed (32' long, 12' wide and 8'high) from one part

You could try using one of these

formatting link
?_dyncharset=UTF-8&q=water+level&x=0&y=0&n=&pn=1&pd=1&pi=1&cn=1&cd=1or if that link doesn't work then go to
formatting link
and search for 'water level'.

It's a long (10m) piece of plastic pipe with sighting tubes at each end - I guess there's no reason why you couldn't extend the pipe if you needed....

There's a bit of a knack to using it, and two pairs of hands are better than one - but once you've got the idea it's probably as accurate as you'll get without going into laser levelling.

Had one myself for a specific job - sold it on ebay afterwards for about the same price as I'd paid for it

HTH Adrian Suffolk UK (nice bungalow for sale in rural Suffolk -

formatting link

======return email munged================= take out the papers and the trash to reply

formatting link
?_dyncharset=UTF-8&q=water+level&x=0&y=0&n=&pn=1&pd=1&pi=1&cn=1&cd=1>Or one of these
formatting link
levels are getting very cheap these days, try Aldi, Lidl, Makro, Toolstation, Silverline etc.

Dave

A two metre straight-edge is easy enough to handle. If you start at one corner and work in both directions, you will be able to get to the far corner in seven hops. Even if you are out by 1/4 inch every time (which is a lot) - that will still be less than two inches (which isn't a lot over the building).

If you can borrow/hire a site level, of course that will be accurate to millimetres over much larger distances.

Finally, if you want real accuracy, cheaply, a garden hose with a couple of lengths of clear plastic at both ends and filled with water will do the trick. (You probably need to get the levels approximately right with the spirit level first. The water tends to slosh backwards and forwards rather than settling to a level.)

I'd use a water level, the cheep lazer levers are exactly that - cheep and very difficuly to use accuratly.

Rick

Thanks for that.

I'd thought about laser levels, but what sort of range do the Aldi/Lidl/Makro ones have?

I guess that I could put in a couple of posts to use a references as if the laser doesn't read (clearly) over 32'.

So I may have to position it (the level) in two places i.e. to give it an 11' (approx) maximum read.

Cheers

Peter

Most people don't know how to use a level properly anyway. You should swap ends every time you mark a point.

Get 25 feet of clear plastic hose from a homebrew shop or similar. Drive a stake into the ground in the middle of the plot so it sticks up two or three feet and fix one end of the hose to that, open end up at the top of the stake. Temporarily fix the other end of the hose next to it, fill the hose with water to within a foot of the ends and mark the water level on the stake. Now wherever you hold the free end of the hose the water level will be at the same height as the mark. You will need to recalibrate occasionally due to thermal movement/evaporation/spillage or if the hose gets stretched or crushed.

You only need the ends to be transparent so a garden hose or whatever will do in between. Be careful of bubbles and air locks.

But what is wrong with using the string line and level you will be using on the blocks?

Much easier to eliminate bubbles if the whole tube is tranparent, and most garden hoses are probably too easily deformed thus varying their volume and shifting the water level. Plus transparent tubing will be less susceptible to being warmed by sunlight, so will reduce thermal variations.

But surely it doesn't matter about volume or temperature variations, because water will always find its own level. You would need to check each end simultaneously of course, which suggests 2 people.

Owain

My £25 Makro jobby reads at well over 50' - came with a set of red gogles to make it easier to see.

Dave

Excellent point Owain. If the water expands it must do so equally.

Dave

You could check at both ends - if the water level at the fixed end wasn't level with the original mark then that offset would be applied to the measurement at the other end. Or you could just do it like I said, and check occasionally that the water still comes to the mark on the post.

What if one end is hot and the other is cold (one end in sun and the other in shade)? The cold water will be heavier than the hot water, so the level at the cold end will be lower than at the hot end.

Simple - use a small solar powered pump to circulate the water.

Dave

Of course - sometimes the solution is so obvious that it's hard to see :-)

Feh, technology for the sake of it. Put a second tube in parallel to the first and set up a thermo-syphon.

Owain

Yes, you can see lakes tipping up on warm days towards the shady ends...

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required