Questions tagged [subfloor]

Structure above the floor joists and below any finished flooring.

Filter by
Sorted by
Tagged with
0 votes
2 answers
60 views

Good approach to preparing badly damaged wood floor for tiling

I'm wondering the best strategy to prepping this for tile. It's 2x9 (actual) joists with 1x8 subfloor and 1/2x2 flooring. The strip flooring is full of gashes and cracks and the whole subfloor has ...
user avatar
  • 17k
0 votes
1 answer
30 views

Need a cheap material to level subfloor

2nd floor subfloor slopes from the outer walls towards the middle. Varies about 0.5in to 1inch depending on the wall and distance to the most depressed area of the floor. The subfloor is 5/8" ...
user avatar
1 vote
1 answer
60 views

Mid 70s home with 3/4 particle board sub floor, need clarification

We bought this house, it was almost all carpet except the kitchen and bathroom which were sheet vinyl. The house smelled musty and the carpet was OLD. It has all been torn out now. I've read dozens of ...
user avatar
0 votes
0 answers
69 views

Unable to drill through second story subfloor

I have squeaky floors on my second story. I bought one of those repair kits with the tool that helps find the joists through carpet. Wherever I drill, no matter which room or what distance I move ...
user avatar
  • 1
1 vote
1 answer
75 views

How to support walls and subfloor in this bathroom

I just purchased a ranch house (with basement and garage underneath) and decided to try to renovate the bathroom. The flooring was linoleum, after taking off the linoleum, I discovered that the ...
user avatar
1 vote
1 answer
56 views

How can you tell if interior concrete floor is sealed? [closed]

I've recently bought a house and removed the existing laminate. I was told when buying the house that the downstairs subfloor was sealed concrete. After removing the laminate flooring I found the ...
user avatar
0 votes
1 answer
52 views

2x6 as floor joist

I am going to be replacing the subfloor in a room, but just noticed that the exiting joists at the end wall (room getting new subfloor is a dining room, room next to it is a bathroom) end at ...
user avatar
0 votes
1 answer
24 views

USG Fiberock underlayment used for tile installation

I reinstalled the tiles in the laundry room and the installer used USG Fiberock, instead of Hardiebacker - as initially told me. He’s telling me that USG Fiberock is good for laundry room. But now I ...
user avatar
  • 31
0 votes
1 answer
54 views

Adding a half inch of height to subfloor for laying floating porcelain tile

I am laying floating porcelain tile that is a half inch thick. I also have to lay down an underlayment under the tile. After accounting for both of these items I come up about a half inch too short ...
user avatar
0 votes
0 answers
47 views

Installing new subfloor directly over old spongy subfloor

I have a 2017 modular home (12 x 54) with an osb sub subfloor that has sheet vinyl loose laid (no adhesive) as the floor covering. The subfloor is getting Soft in several locations. I feel like it may ...
user avatar
0 votes
1 answer
89 views

Installing 3/4" plywood underlayment over 1/2" subfloor

I've seen many variations of my situation discussed here, but I'm new to all of this and I want to make sure my plan is sound. I'm finishing a bonus room over the garage that currently has only a 1/2&...
user avatar
1 vote
2 answers
71 views

Can I add 1/2-in. Plywood/OSB to my subfloor?

I'm looking into finishing my attic and turn it into a man cave. I had someone look at the joist and they said it was up to code for adding a floor. There is already 1/2-in. OSB subfloor in place, but ...
user avatar
  • 13
0 votes
0 answers
33 views

Reconstructing sub floor after long term leak

My 1930s house is built on a slope and in a room on the ground floor over the lower part of ground that used to be the kitchen I e found an old slow leak when converting to a utility room. The leaks ...
user avatar
0 votes
1 answer
36 views

Subfloor hole/rot and stains - Is my approach correct?

Planned to replace carpet with wood and pulling up carpet revealed areas with water/pee stains and rotting/crumbly plywood subfloor. A couple of areas that were rotting had black dust but it does not ...
user avatar
  • 1
0 votes
1 answer
68 views

XPS to raise subfloor?

Regarding to my old problem: Tiles above concrete, with electrical conduits I am thinking about using XPS to raise my concrete attic subfloor, so that I can bury existing electrical conduits. Details: ...
user avatar
25 votes
4 answers
3k views

Replacing hardwood floor in 100 year old house with no subfloor

This is a 100-year-old, single family house in Washington, D.C. The floors are aged and worst of all terribly squeaky. The main issue we are trying to solve is to not have the floors squeak. Unless we ...
user avatar
  • 451
1 vote
1 answer
125 views

How to support subfloor because of gap between floor and joist

There is a beam that runs down the center of our house (in the basement). Floor joists are hung on both sides of this beam. On one side of the beam there are gaps between the subfloor and joists (...
user avatar
  • 1,308
0 votes
0 answers
27 views

Are Vinyl floorings designed for High traffic best on Basement concrete?

Have to install Vinyl flooring on my concrete basement. my basement flooring is not 100% flat. I see a lots of 1/8" low spots and some places have 1/4" low spot within 10 feet. I have to ...
user avatar
  • 570
0 votes
0 answers
46 views

Sister i-joist for subfloor install?

I am doing a small bathroom remodel that turned big...now replacing a 4' by 4' section of subfloor thanks to discovering surface mold on the subfloor (no rot). The joists are 16" on center and lo ...
user avatar
  • 1
0 votes
0 answers
58 views

12x24" Porcelain Tile over 2x6x1.5" T&G Spanning 48" Beams

I have some questions in regards to installing 12x24" porcelain tile over 1/2" plywood underlayment that sits above 2x6x1.5" T&G subfloor that is supported by posts and beams on 48&...
user avatar
  • 11
0 votes
0 answers
38 views

Kitchen subfloor replacement

We purchased this home three years ago and have 18x18 ceramic tile in the kitchen and foyer that is cracking. I removed a portion to see what is going on and the old plywood definitely needs replaced. ...
user avatar
1 vote
0 answers
54 views

Subfloor prep for tile in old house

Photos were too big to upload, here is a link: https://drive.google.com/drive/folders/1DTvfB7t1N6GmmzYFvEv53RH2NSWzB4H- Goal: I want to tile the kitchen and breakfast nook w/ 12 x 12 ceramic (was ...
user avatar
  • 11
1 vote
2 answers
159 views

How much gap is acceptable with tongue-and-groove OSB subfloor?

I am installing subfloor in a old house attic. I am having a hard time getting the tongue and groove all the way in. Will I fail inspection with gaps this big?
user avatar
0 votes
1 answer
53 views

How to make tile even

We have vinyl plank flooring throughout the house and is directly on the subfloor. We want to add tile to a bathroom but adding cement board on top of the subfloor and the height of the tile would ...
user avatar
0 votes
0 answers
221 views

Self-leveling concrete prep: how to fill large gaps?

[Note: Variations of this question have been asked before, but the ones that received answers were talking about sealing gaps for other purposes. So here goes.] TL;DR: I have 3/4”-1” gaps at the edges ...
user avatar
  • 101
0 votes
1 answer
48 views

How to seal old subfloor with coper sulphate preservative?

I purchased an old home a month ago. Slept there 3 different occasions for one night at a time and every time I felt unwell for days. Last time after removing the carpet I noticed copper green residue ...
user avatar
0 votes
1 answer
59 views

Is it sufficient for toilet flange to be screwed to floating subfloor only?

I have concrete slab basement floor with 3" cast iron sewer pipe sitting about 3" below the surface of concrete. To access this pipe I have a hole about 6" wide around this pipe (See ...
user avatar
0 votes
1 answer
49 views

DMX with Expansive Soils

I live in Colorado and have to deal with expansive soil caused by bentonite. Our basement slab is intentionally designed to float with the expansive soil and I have personally observed shifts in the ...
user avatar
  • 417
0 votes
0 answers
54 views

Why are the edges of our subfloor wet after rain, but the walls are completely dry?

Our house has a stucco exterior and a dirt crawlspace, part of the crawlspace is wet, but there isn't much water pooling down there. Where the water is pooling, the subfloor is completely dry. The ...
user avatar
  • 1
2 votes
4 answers
326 views

What type of plywood to use on top of a thin subfloor

I'm trying to prepare floor for a new laminate flooring. I noticed that the thickness of the subfloor plywood is only half an inch. I researched it is recommended to have at least 5/8-inch or 3/4-inch....
user avatar
  • 390
1 vote
0 answers
34 views

Plywood over hardwood underlying a poured bathroom floor?

In this 1954 New Mexico home, in the bathroom there is plywood apparently laid over the hardwood floors. But it seems to be actually sunk below the 'grade' of the hardwood. Additionally, there is what ...
user avatar
3 votes
1 answer
99 views

Is my approach to installing wood subfloor over concrete correct?

I recently purchased a new home in South Carolina, and was planning to extend the existing hardwood throughout the rest of the ground floor. Once I began to remove the existing carpet, I saw that ...
user avatar
0 votes
2 answers
62 views

Fixing chips on the edges of a basement slab

I'm planning on redoing the flooring in a basement room which has a concrete slab in a 1974 Seattle house. The current carpet, which I've already removed, will be replaced with LVP. After removing the ...
user avatar
  • 135
0 votes
0 answers
121 views

Is it necessary to use roofing felt paper between shed floor joists and subfloor

I am building a 12x14 shed with pressure treated 2x6 on pressure treated 4x4 (resting on 4 inches of 57 stone). Before I put the pressure treated 3/4 plywood subfloor on should I also lay down felt ...
user avatar
17 votes
2 answers
2k views

Is 3/16" plywood subfloor sufficient for a shower floor?

My contractor is installing a 3/16" plywood as a shower pan subfloor on 16" floor joists. It is for a curb-less shower. I think they did that because they built the floor too low to allow ...
user avatar
  • 343
1 vote
1 answer
254 views

Best way to correct one inch dip in middle of second floor master?

We’re installing hardwood flooring in our second floor master bedroom. House was built in 1993. When we pulled off the carpet we realized the floor dips in the middle. The room is 18 ft (north-south) ...
user avatar
2 votes
2 answers
310 views

Can screws be used on floor joists?

I recently had a contractor repair damage to my subfloor and joist. In addition to installing the new Joist's he also cut pieces of wood (same wood as the joist) into 2ft pieces and screwed them into ...
user avatar
  • 21
1 vote
1 answer
183 views

How can I tell if I'm looking at original hardwood or subfloor?

I ripped up a portion of my carpet and found wood underneath. Problem is: I can't tell if what I'm looking at is just subflooring or potentially the original hardwood. I've ask people who know more ...
user avatar
1 vote
1 answer
154 views

Accidentally ran some plywood flooring parallel to joists on my shed. How big of a deal is it?

I'm building a shed/barn and apparently had a bit of a brain fart when nailing down the plywood floor sheathing. I nailed it down parallel to the joists (like t1-11 sheathing on an exterior wall), ...
user avatar
0 votes
1 answer
104 views

Solid wood flooring - Possible sub-floor issue

I am in the process of installing solid wood flooring in the living room and I have just removed the existing laminate flooring and underlay to find the concrete subfloor is in great condition except ...
user avatar
0 votes
0 answers
28 views

Replacing sub floor, that is under a concrete floor

House was built in the mid 60s. It's on piers with a craw space. While having it leveled, we discovered rot under the half bath. The water leak is fixed. However discovered the sub floor that needs ...
user avatar
  • 1
1 vote
2 answers
309 views

How to prepare this uneven concrete floor for tiles?

We are planning to lay a tile hearth in our fireplace but unfortunately, the concrete subfloor is quite uneven, see pictures. We have had this fire opening widened, so the black damp proof course is ...
user avatar
3 votes
1 answer
718 views

What are the actual dimensions of a 4x8' subfloor plywood panel

If the joists are 16"oc and our plywood is exactly 4x8' and we have to allow 1/8" gap between our plywood panels wouldn't it shift the next panel by 1/8" and then the next by 2/8" ...
user avatar
0 votes
1 answer
40 views

Can I use a flooring underlayment in conjunction with a LVP plank that already has an underlayment built-in?

I'm replacing an old LVP floor, which required an underlayment, with a new brand LVP that has an underlayment built-in. I'd think that to mitigate sound and vapor, a reasonable thing to do is to ...
user avatar
1 vote
1 answer
113 views

Can I screw through wood floor and plank subfloor to joists to prepare surface for tile?

I’m renovating my 100year old house’s kitchen and found that the old existing tile was attached directly to hardwood flooring. This explained why so much of it was cracked even though it is the only ...
user avatar
0 votes
0 answers
29 views

Can I apply self leveler primer over painted(primer) wood subfloor

The instructions say the wood needs to be bare wood for all the self leveling compounds like Henry/cbp/mapei but there are also plenty of videos that show it being applied to various levels of clean ...
user avatar
  • 1,521
1 vote
2 answers
171 views

Uneven Subfloor in the 2nd story

I am installing laminate flooring in my 2nd story and have come across this in a hallway. The floors otherwise are pretty level, but there is a bad hump where these two pieces of plywood meet. About 1/...
user avatar
  • 21
0 votes
1 answer
69 views

Replace strips of tongue and groove subfloor

A corner in my laundry room is sinking/rotted, the construction is tongue and groove with particle board on top. I suspect the rot probably goes into the tongue and groove planks. How do I replace ...
user avatar
0 votes
0 answers
18 views

Subfloor and underlayment sizing for LVP glued down flooring

I've read many different topics on flooring but haven't seen an answer specific to my questions, so I'll post them here. Thanks for the help in advance! The back-story: I ripped up 40yr old carpet ...
user avatar
0 votes
0 answers
37 views

What subfloor should I use in the bathroom for LVT?

I need to fit Luxury Vinyl Flooring throughout the top floor of my house, however the floorboards in the bathroom are all at different heights. I know that LVT requires an absolutely flat surface, so ...
user avatar

1
2 3 4 5
10