Thread: Floating floors - what to do?

Ply first then fix flooring to it. Make sure you get the correct high density acoustic insulation for the floor.
http://www.timber.net.au/images/down...tic_floors.pdf

Originally Posted by rwbuild

Ply first then fix flooring to it. Make sure you get the correct high density acoustic insulation for the floor.
http://www.timber.net.au/images/down...tic_floors.pdf

OK to use 14mm thick boards?

As the sub board on top of the insulation...NO.... way too much flex with all those joins but 14mm sheet as sub base but it has to be premium ply at that thickness to eliminate sheet distortion, basically 1st grade marine ply, new formwork ply would be ok ,14mm flooring yes as the finished floor....yes

Thanks for the link, RW. I imagine new formwork ply would be a fair bit cheaper than marine ply. Any ideas about yellow tongue?

Do you think screwing down the old squeaky boards is worthwhile? I was wondering if the layers above them would be sufficient to spread the load.

The current plan is a layer of AngelStep 484 Gold 12 mm first, 19mm ply or similar and then 20mm spotted gum t&g.

mick

Yellow tongue will be ok, definitely screw down the old floor first.

Originally Posted by Glider

The current plan is a layer of AngelStep 484 Gold 12 mm first, 19mm ply or similar and then 20mm spotted gum t&g.

mick

Hi Mick

Your plan to increase the floor thickness by a total of 51 mm will have a lot of flow-on consequences:

• Presumably it will be done in all rooms simultaneously otherwise you will have a step of 51 mm between the old and new floor heights,
• Will you also raise the skirting boards - if not, then you will reduce their visible height by 51mm - could be desirable, or not?
• You will need to cut a clearance strip off the bottom of every door so that it can swing freely - including the front door. Will the new floor thickness then be visible under the front door?
• Will you raise all kitchen cabinets and re-position them on the new floor height? This may require alterations to plumbing, wiring and tiling. If you leave cabinets where they are and raise the floor around them, you will reduce the effective bench working surface heights, which may be uncomfortable.
• What about the bathroom?
• What is your ceiling height? Will the reduction be significant?

So many questions from such a seemingly simple job.


Cheers

Graeme

Originally Posted by GraemeCook

Your plan to increase the floor thickness by a total of 51 mm will have a lot of flow-on consequences:

• Presumably it will be done in all rooms simultaneously otherwise you will have a step of 51 mm between the old and new floor heights,
• Will you also raise the skirting boards - if not, then you will reduce their visible height by 51mm - could be desirable, or not?
• You will need to cut a clearance strip off the bottom of every door so that it can swing freely - including the front door. Will the new floor thickness then be visible under the front door?
• Will you raise all kitchen cabinets and re-position them on the new floor height? This may require alterations to plumbing, wiring and tiling. If you leave cabinets where they are and raise the floor around them, you will reduce the effective bench working surface heights, which may be uncomfortable.
• What about the bathroom?
• What is your ceiling height? Will the reduction be significant?

Thanks Graeme, all good points. All the furniture and carpet has been removed from the flat. The old bathroom will be stripped out and replaced & a second bathroom created on the other side of the apartment.

- The plan is to use the same flooring system throughout the flat, except for the bathrooms of course.
- Skirting boards are about 400mm high.
- Also about 400mm from the bottom of each door panel so no visible difference. The bottoms of the architraves stand proud so they'll have to be cut under with an all purpose tool. We can deal with any gap under the front door with a draught stopper.
- We are actually moving the kitchen to the other side of the flat. The flooring will be laid first and then the benches installed at 1000mm height which we greatly prefer.
- Ceiling height is 2700mm.

The big question is whether the multi-layered system insulates for sound as well as the old carpet with foam underlay. Certainly the squeaks will disappear. Unfortunately our neighbour below won't allow acoustic testing so we have to take a punt.

Cheers,
mick

Originally Posted by Glider

- Skirting boards are about 400mm high.
- Also about 400mm from the bottom of each door panel so no visible difference. The bottoms of the architraves stand proud so they'll have to be cut under with an all purpose tool. We can deal with any gap under the front door with a draught stopper.

400mm or 40mm?

Why not pull up the old floors?

If the downstairs guy is being a dick about it and won't help, don't concern yourselves. I'd just pull up the floors, lay down insulation between joists, put down yellowtongue then nice floorboards above.

I did this with two flats in Double Bay and it worked a treat.

You certainly wont get the loss of 50mm from all those sedimentary layers!

It was a super fast job too.

All good, Mick. Essentially a rebuild, rather than just lifting the floor.

My place also has baltic pine skirtings - 400 mm in the public rooms and 300 mm in the rest. They just do not make stuff like that anymore. In my view, it would be a shame to effectively cut that 400 mm to 350 mm by covering it with flooring. Is it feasible to raise the skirting?

Sound insulation is so difficult to get right - sound sneaks through the smallest holes. Years ago an employer had a board room built with extremely expensive lead/foam veneer panelling. The panels may have been soundproof. The aluminium extrusions in which they were mounted certainly were not. A $250,000 failure.

Woodpixels suggestion might be worth looking at unless the joist space is shared with the apartment below's wiring. Is that wiring rated to have insulation laid ontop? Potential fire hazzard and/or legal risk?

My major concern remains the threshhold from outside. Perhaps you will need to design in a new door step?

Finally, how good is the baltic pine floor? I keep visuallising 80 year old forest grown baltic against modern materials. One option, maybe a pipe dream, might be to carefully lift the entire floor, fit yellow tongue, the acoustic tiling, then refit the old baltic floor. It will match perfectly with the baltic skirting, architraves and doors.


Love these sorts of challenges.

Graeme

It may be a little late in the planning stage for this, but Hempcrete may well be an excellent solution to fill up in between the floor joists with for acoustic insulation (as well as heat/cold). It comes in bags that you mix up into a dryish fluid and pack in to wherever it's needed. If the website is to be believed it's a wondrous building material.

Hempcrete.com.au: The Australian Hempcrete Technologists

Originally Posted by GraemeCook

Finally, how good is the baltic pine floor? I keep visuallising 80 year old forest grown baltic against modern materials. One option, maybe a pipe dream, might be to carefully lift the entire floor, fit yellow tongue, the acoustic tiling, then refit the old baltic floor. It will match perfectly with the baltic skirting, architraves and doors.

To be honest Graeme, I find Baltic flooring a giant PITA. I have it here and it looks.....ok I guess (but no better than Cypress)....where it isn't disintegrating from normal traffic. Then it becomes a peeling pain in the butt. It's just too soft for flooring IMO. If you have a rolling office type chair on it then it becomes a nightmare, even with softer polyurethane wheels.

Originally Posted by GraemeCook

Finally, how good is the baltic pine floor? I keep visuallising 80 year old forest grown baltic against modern materials. One option, maybe a pipe dream, might be to carefully lift the entire floor, fit yellow tongue, the acoustic tiling, then refit the old baltic floor. It will match perfectly with the baltic skirting, architraves and doors.

Why not? Label each board with a number, pull it up in sections and do it from left to right.

Difficulty will be getting it up without it breaking or pulling the nails through. Maybe one could test this on a "discrete corner" (in a cupboard?)

not to be a wet blanket, but ...

do you actually own the baltic pine floor? or is it part of the common property?
Ditto with respect to any plumbing and wiring that might need moving or installing.

assuming the body corporate is on side, perhaps the best option is to remove the existing flooring and strip the skirting boards.
Reinstalling the boards to accommodate a thicker floor is not that difficult.