Archive for Downsizer For an ethical approach to consumption
|
Nick
|
Rotating laser levelsAnyone used one of these?
I wish to mark out a horizontal line around the inside of a room around two inches above the floor. But the floor is uneven, and the line will not be. A rotating laser level thingie seems the ticket. Can they be used to mark a point below their resting height, ie, can they be tipped down, anyone know, as standard? I can buy one for only a few quid, or hire one, but I thought I'd ask before making the trek into Hereford.
|
alice
|
All the time. You just make a trammel (sp?) then mark the lower line you want, below the laser line.
|
Nick
|
Oh yeah. D'oh.
But, that won't help me spot the highest point of the floor, easily.
|
alice
|
Nope. You've lost me there. When you go round with your trammel, all will be revealed - surely? Or use a ruler?
|
alice
|
Oh, and cheap ones don't like being used in the cold.
|
Nick
|
The level will be about three feet off the floor. So will the line. Be handy if the line was as close to the floor as possible.
|
alice
|
Don't use the tripod then 
|
onemanband
|
set up laser - any height
measure from laser line down to floor to find highest spot (shortest measurement)
It is usual on site to mark 1m above finished floor level(keeps the maths easy)
So if your highest point is say 750mm to laser line and you want to add 75mm of screed and 25mm floorboards, then the laser line is 650mm above the finished floor level.
Mark laser line on wall, measure up 350mm and that will be 1m above finished floor. Then transfer 1m line around walls (either measuring up or resetting laser to 1m height).
Once you have a 1m line it is easy to work out height of the various materials making up the floor.
Or plonk laser on floor, find highest spot, subtract thickness of material and use that measurement down from line
|
Nick
|
Don't use the tripod then |
Yeah. Some idiot might have left a 400kg bag of sand in the middle of the room. 
|
Woodburner
|
What is the ultimate goal here? Surely not simply a perfectly horizontal line around the room? 
|
Hairyloon
|
What is the ultimate goal here? Surely not simply a perfectly horizontal line around the room? |
I'm guessing at a level floor.
Nick
|
Yep. My garage floor is concrete and a bit uneven. Plan is to nail wood battens to the wall and use these to re-lay the floor with a couple of inches of fresh concrete. So, I need to find the highest point of the floor, and work from there, horizontally.
|
Woodburner
|
The chap who did my kitchen floor (it was nearly two inches lower in the middle) used self levelling cement. 
|
Nick
|
That's going to be the final layer, but its much more expensive than regular cement, and unless things have changed shouldn't be used for such depths. I'll look again, tho.
|
chicken feed
|
That's going to be the final layer, but its much more expensive than regular cement, and unless things have changed shouldn't be used for such depths. I'll look again, tho. |
you can get a deep base compound it can be used upto 50mm takes 3 hours to set but is expensive £17.99 for a 20kg bag last week.
if you are using the right laser level you can get your floor level (OH uses one for work for just this type of job)
Nick
|
Thanks. I'll go talk to a hire shop and find the right one. Ive got a difference of up to 70mm in places, and 36m2 to cover. And I've not won the lottery.
|
onemanband
|
Or there's the old skool method of screed rails.
Set scaffold tubes or timber batons on concrete dabs/bricks/slate at finished height at about 4 foot apart. Rule concrete off to top of rails and remove rails and backfill as work proceeds. Rails can be set up with a long spirit level (or a laser)
Are you laying concrete or screed ?
Screed can take practice to get it level and smooth and I would recomend screed rails on a large area.
If concrete is fairly wet it should tamp and float fairly level, although screed rails will make it easier to get it roughly level before tamping
|
crofter
|
You should not need a self levelling final layer if you pour and level the floor as onemanband suggests. Are you going to drive a car into the garage? If your concrete is only a couple of inches thick, it might crack... Also, you should paint pva glue (diluted 3:1 approx) on the old concrete, then another coat of stronger pva (diluted 1:1) before you pour the new concrete, to help bond the new floor onto the old.
|
onemanband
|
Wot Crofter said
I was going to mention thickness - will depend on usage and condition of existing concrete, although if you have 70mm difference in existing concrete levels and you lay 2 inches over the highest spot then that will be 4-5 inches concrete elsewhere.
2 inches on pedestrian areas will be ok. 4 inches needed where driven over.
reinforcing mesh is a good safeguard and you could then get away with 3 inches on driven areas
Oh and new garage slabs are built with extra thickening at the entrance. Make slab at entrance a good foot deep (maybe add some rebar) if you are going to drive in regularly.
|
vegplot
|
Thanks. I'll go talk to a hire shop and find the right one. Ive got a difference of up to 70mm in places, and 36m2 to cover. And I've not won the lottery. |
That's not a garage, that's a house.
Nick
|
It's a third the size it was.
There's already a slab, but its cracked, hence the new layer. It's unlikely I'd put a car in it. What a weird idea! Cars have weather proof paint. Lawn mowers and such need locking away.
|
Home Home Home Home Home