Hardwood over shiplap planking

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Posted by: from Ottawa
11/18/2012 at 5:52:15 PM

Is it advisable to lay new 2 inch wide @ 3/4 inch thick hardwood flooring directly over shiplap planking, the planking is 50 to 60 years old.

The shiplap is laying at a 45 degree angle on the joists, +1/8 inch gaps between the boards (dried out).

I was thinking about removing the original 3/4 " particle board sub floor that is nailed on top of the shiplap and then laying the harwood. I wanted to do this so I would end up flush with the other floors.

If not, how about gluing (construction adhesive) and screwing 1/4 inch thick plywood directly onto the shiplap and then laying the hardwood flooring.

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Date/Time11/18/2012 at 7:21:47 PM

Take out the old planking and use either 5/8 or 3/4 ply glued and screwed. As the new base for the hardwood. It'll be more squeak free (depends on the rest of the framing), provide a solid base for nailing into and will keep you flush with the other floors. It's only a small time investment in demo and installing the new sub floor.


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Date/Time11/18/2012 at 7:33:01 PM

You can lay hardwood directly over the original subfloor, but I would advise against it. You will probably end up with a squeaky floor. The particle board has no buisness being used as a subfloor, so I would remove it. Glue and screw into the joists the new plywood over the original subfloor. The thicker the plywood the better but i would say at leat 1/2". If you are worried about the height differance, you can use engineered flooring which is available in smaller thickness than 3/4".

FYI what you have is a standard subfloor for the era. They were layed with a small gap on purpose. True shiplap has half the thickness removed from the edge so that the boards overlap each other. Usually used for siding, and ships of course, back in the day of wooden ships.

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Date/Time11/18/2012 at 7:43:53 PM

This is not a general situation as all installs hardwood require level solid base as it will not be a floating floor. Best result of install will be from good preperation, the particle board needs too go regargless, then acess the planking level screw and glue as required.

Do not purchase any products till you have accessed floor. There is so many options, look into infloor heating, agillia screed self leveling cement. Do not advise on directly over will need leveling, your last mentioned option, gle screw 1/4 would work best again how level is the floor, mesh and scratch coat first call I have 100 of ft of mesh available, cold insulate and install good quality 20 yr or better click floor over a R5 insulation. Many options available.

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Date/Time11/18/2012 at 7:53:06 PM

You can buy 1/4" plywood underlay specifically for this purpose (it is smooth face but costs less than 1/4 inch "A" grade sanded one side plywood). This stuff comes in 4'x4' or 4'x8' sheets. It will work fine if you screw it down properly.

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CH2RI in Mississauga
Date/Time11/18/2012 at 8:29:55 PM

Tear out the 3/4" particle board. Screw down each shiplap board (I'm assuming 1x6) with at least two 2" drywall screws to remove any squeeks in erach board to the joists. Lay down 1/4 sub floor and screw it down with 1" drywall screws. Nail your hardwood floor to that.

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Date/Time11/18/2012 at 9:43:10 PM


Stewart here of Sct Floorcoverings. I would recomend first to remove the particle board. Then screw planking tight to the joists.Then Traverse Mount( Lay opposit way to the way the joists are aligned) 3/8th thick exterior Grade Spruce Plwood, Screw Plwood to the joists and planks. Then lay the Hardwood.

Best regards,

Stewart, Sct Floorcoverings


Ph# 289-814-3023

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Alexander from Top Choice Flooring in Newmarket
Date/Time11/19/2012 at 10:21:21 AM

Put a new 5/8" plywood as a subfloor, install a new hardwood flooring using staples and install reducers or t - molding to finish the job.It shold be OK , Do not mess with the glue.The subfloor is very important. Chipboard exceptable by code but plywood will do much better.

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