New addition's subfloor is 5/8" higher then the existing house subfloor

Flooring Forum - DIY & Professional

Help Support Flooring Forum - DIY & Professional:

Guppy1026

Member
Joined
Nov 23, 2022
Messages
7
Location
Virginia
20221123_163847.jpg
 

Guppy1026

Member
Joined
Nov 23, 2022
Messages
7
Location
Virginia
The addition is to the left, the middle is the subfloor of the existing house, and the right is the existing engineered wood flooring. The addition was to be a seamless transition of wood floor. Help, how can this be fixed?
 

Incognito

Professional
Pro
Joined
Jul 5, 2011
Messages
1,318
Location
Los Angeles, CA
RFC----Request For Clarification. Exactly what flooring is in that photo.


Thinking of the LEAST offensive of a few potential solutions

First thoughs turn to a custom threshold/transition matching (?) wood/stain/finish.

It will not meet ADA requirements and will actually be something of a trip hazard but I'm having much bigger objections to the next few solutions that come to mind.

All my next ideas would involve tearing out some/or both existing floor and the new subfloor to "split the difference" minimizing that 5/8" sudden drop between the addition and existing structure.

Give us some more specifics please and draw back on that photo to give more perspective. If a contractor did this he should NOT get paid until you can be happy with the solution.
 

C.J.

Supporting Member
Supporting Member
Pro
Joined
Apr 23, 2021
Messages
2,631
Location
Over here now
I’m assuming the new subfloor is supposed to be lower than the finished floor height of your existing flooring so that when you install new floor in your addition it should flush out with what is currently there.

If that’s the case then it looks like your contractor gets to remove the subfloor and lower the joists. Any other solution will have a transition with a trip hazard as Incognito mentioned.
 

Guppy1026

Member
Joined
Nov 23, 2022
Messages
7
Location
Virginia
That is 12ft of open floor across the room. This is the pulled back picture of the area. The new engineered hardwood floor to put in the addition matches the thickness and matches the style and color of the existing floor.
 

Incognito

Professional
Pro
Joined
Jul 5, 2011
Messages
1,318
Location
Los Angeles, CA
I’m assuming the new subfloor is supposed to be lower than the finished floor height of your existing flooring so that when you install new floor in your addition it should flush out with what is currently there.
i
If that’s the case then it looks like your contractor gets to remove the subfloor and lower the joists. Any other solution will have a transition with a trip hazard as Incognito mentioned.
I was kind of assuming he was not considering MAJOR STRUCTURAL work as that would generally, by this phase of the construction have a snowball rolling downhill on other considerations..........plumbing/electrical/HVAC/whatnot. But of course that's the obvious and correct direction toward fixing this. Maybe there's not that much to do besides pulling up the subfloor and lowering the joists. I'm not very good at optimism. How does that usually work out? I've only been pessimistic for 62 years. So I would not know.
 

Incognito

Professional
Pro
Joined
Jul 5, 2011
Messages
1,318
Location
Los Angeles, CA
Are YOU doing the entire addition/structural work here or do you have a General Contractor or subcontractors responsible for the height discrepancy? It makes a difference because it affects your budget concerns.
 

Guppy1026

Member
Joined
Nov 23, 2022
Messages
7
Location
Virginia
Nailed in flooring. General contractor, when he found out with the wall removed he said he can fix it by taking out a couple feet of the existing engineered hardwood flooring in the house and level it out and re-lay down the hardwood. "We won't see it" but it feels like we are just kicking the can down the road until it becomes the "issue" at the end of the project.
 

Incognito

Professional
Pro
Joined
Jul 5, 2011
Messages
1,318
Location
Los Angeles, CA
Nailed in flooring. General contractor, when he found out with the wall removed he said he can fix it by taking out a couple feet of the existing engineered hardwood flooring in the house and level it out and re-lay down the hardwood. "We won't see it" but it feels like we are just kicking the can down the road until it becomes the "issue" at the end of the project.
His solution isn't crazy but I'd surely want more than "a couple feet" to soften the ramp. I would probably "split the difference" by going back equal distance from the center. Take away subfloor/structure on the new and shim/add on the existing. This can work if you have adequate stock to replace the flooring you might choose to demo to create a ramp up to the new.

From the photo I'd be thinking to go back just shy of that doorway on the new work. He's thinking ONLY tearing back your existing wood to make the same ramp? Wouldn't be my first inclination. 5/8" isn't something you wont notice over "a couple of feet".

A couple is 2 BTW. When you have a couple's party no one should show up with 4/5 plus persons.
 

JPfloor

Supporting Member
Supporting Member
Joined
Feb 27, 2022
Messages
293
Location
New York
How many square ft. of the existing floor is there? Is it feasible to rip the existing out, install new plywood, and install all new hardwood? Might be less costly than trying to lower the joists. Maybe just have the height difference in a couple of doorways somewhere? If a ramp is the only answer I’d want at least 6’ back to accommodate 5/8th”.

Man I hate to say this, I know everybody makes mistakes, but that’s a doozy.

And I gotta ask another question. With all this going on, why in the world would they put up the base molding?
 
Last edited:

Chicago77

New Member
Joined
Nov 23, 2022
Messages
3
Location
NorthEast
For what its worth in my last ABB that I was redoing I took the easier route and floored over about a 1/4 in transition over about 2.5 feet where i though it wasnt going to be thattt noticabel. Turns out it is definitly noticable when you walk on it. Its not bad, but definitiley there.

In my humble opinion 5/8" lift is going to be very noticable unless its really far spread out. You would almost want to lift the subfloor and shave down the joist.

Im also curious why the trim is already in place if this is an addition.
 

Guppy1026

Member
Joined
Nov 23, 2022
Messages
7
Location
Virginia
I set a piece of trim down to better show the three different heights, the old subfloor, new addition subfloor and existing flooring. The area is large
 

Attachments

  • 20220926_140548.jpg
    20220926_140548.jpg
    3.6 MB · Views: 0
Top