I need to level my subfloor. it’s like an ocean, dips in both direction, but mostly between the joists. I am putting down a layer of 1/2″ plywood first, so I havce two chances to get it level.
I have been told to not use a self leveling compound because nailing doen the flooring just breaks it up.
I am planning on using layers of building paper, but am clueless where to start.
Any suggestions?
Listeners write in about fireplaces and ask questions about whole-house ventilation, traditional porch flooring, and gutter sealants.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
use beas of PL Premium about 4" oc when you overlay this with the new 1/2"
That will take care of 90% of the problem, then you can skim floor leveror to deal with anything left.
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Thanks piffin,
I assume the beads of the const. adhesive will flatten out more at the high points, but when I screw down the playwood isn't just going to pull it down in the low areas? Would letting it set up a bit before I screw it down help?
I have been away from using my my tools for a few years and am a bit gun shy.
Just screw it down at the joists and give the glue a day or two to harden in between before adding much traffic or screws there in the field. That way the beads there will have set up and act as shims, while still glueing the two together.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I think I'd go with your method. It's quick, easy and actually has a chance of bonding the two layers together.
I can't help but think multiple layers of roofing felt or shingles (!) would compress over time and cause nail pops/squeeks if screws were put anywhere other than the highpoints.
Beer was created so carpenters wouldn't rule the world.
Yes. It is too late for this guy now, but if the first subply is sagging, it will not do much to help the next layer be any stifer when he just adds loose scrap. And no glue means greater chance of squeaks.
The glues makes the two plys perform as one with some diaphragm action to stiffen it further.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Depending on how bad it is you could do the successive layer thing. We will pull a string across the floor and start with thin plywood in the low areas and stairstep the thin plywood back until it met the string. Use adhesive with this thin wood. It helps.
Then we will use a good leveling compound to level out the stairstepped edges. After this then we put down full sheets of plywood with glue and screws. This has always worked well for us.
James
from his description, his problem is flattening it, not leveling it, which is what you describe.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
What I am suggesting will work either way. The string is straight whether it is level or not. Most of the time we were just flattening the floor.
James
Yes I need to flatten it. If I level it I may not be able to get out of the back door :) .....and then I'd have to account for the curvacute of the earth too.
What is you final floor finish going to be? This will effect what to use to level or flattern the floor.
I am using Junkers prefinished oak veneer, about 11/16" thick and about 8" wide, tongue and groove.
Also, getting varied opinions on whethger to staplw or nail it down (l shaped nails from gun).
Any advise...anyone?
Thanks all!
Looking at the install book on the Junkers web site, they suggest using layers of roofing paper or sanding the sub-floor level. Really depends how far out the floor is. You might need to start with pieces of 1/4" plywood in some places. Then cover with 1/2" plywood for nailing the new floor to. Staples for the sub-floor, nails for the finish floor.
You could use a floating floor and a leveling compound. But I did not see one at Junkers. last i used was Harris-tarket (spelling).
Remember flat and level are not the same thing.
I have never tried the following but I don't see why it would not work. Set up a Lazar and find the highest point. Then install screws every 2' on the joist using the highest point as the reference height. Use plenty of glue and screw the plywood down. The first layer of screws would set the height and the glue would take up the space.
Like setting leveling plates with grout for steel buildings.
I like that idea! Any fine tuning could be made up with layers of roofing paper befroe the flooring planks are nailed down.
Thanks,
Jay T.
Wear knee pads.A Great Place for Information, Comraderie, and a Sucker Punch.
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
go and get some broken bundles of old three tab shingles from a supply house and lay them in the lowspots. I did this on my home before screwing 1/2 plywood down for a strip oak floor, worked great
Thanks for the suggestion. I have started with layers of 1/16" roofing paper and it is working out OK. Just a lot of trial and error.
Jay Thomas
Hey Hiker,I second the suggestion by Steve Thomas. I've used three tabs before and it works pretty well. My method is something like this. Figure out where your largest dips are and create a straight edge to use across the high points. Drag the straight edge across the dip and use a construction crayon to highlight any space that is 1/8" or bigger, every 6 inches or so. Your end result should outline where you need to lay the shingles. Lay in your biggest pieces then cut and shape smaller ones to fill your outline. Now... do it again. Each time, the area to fill should be smaller until you have a relatively flat surface to work with. One note though... I try to use 3/4" plywood to re-cover the floor after I've laid in the shingles. This helps keep it flat. Beware of your fasteners too. I've used as much as 10 layers of shingles in one spot and had to use a longer screw to get a positive connection. I was hesitant at first about this method but I've done it several times and so far, so good. Rob
Thanks. I am using a similar method. I am using an 8' llong evel for a straight edge. I slid a small sheet of 1/16" thick roofing paper back and forth in the gaps until I meet resistance and mark those points. Once I'm finished with laying the 1/16" areas I'll go back and add more layers as needed.
I find it quickest, easiest , makes for the best job to strip the sub floor down, expose the joists, and work up from there.
I've worked from the high spot and shimmed everything up to meet it.
I've worked from the low spot at a doorway and cut / planed everything down to meet it ...
and I've started in the middle and done a combination of both.
the job will tell U which method is best.
easiest is use the high spot as the reference and overlay the joists with tapers cut from 2x stock.
shoot a level perimeter ... tack nails or drive screws at each corner to that height.
run a string line all the way around the room ... then sight / string line across the room as needed.
simply measure from the string to the joist and cut the shim.
run a bead of const adhesive and tack the shim to the joist.
lay down some new 3/4 and you're set.
each and every time I try to take "the easy way" out and not open the whole damn mess up I end up regretting it. Spend way too much time playing with the small adjustments to try and get close to flat or level.
Jeff
Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Directions call for seating a 48inch wide plastic shower base in cement when wanting to level the floor the 3/8inch variance from one side of the shower base to the other.
Not feeling comfortable with the idea I'm thinking perhaps shimming up as the earlier posts define and then covering with a 3/4inch plywood before seating the base would do the trick?
Might this be a way to go?
Thanks
I hear you brother, but this is not just one room. It's a living room connected to a dining room connected to a kichen. Way to much to cut out arond center walls and cabinets, most of wich run parallel to the joists. Plus, there are a series of 4x12s running across the living room and extending out to support a cantivered deck.
I'm going to flatten the #### out of it the best I can and live with it.
Thanks