Hi All,
I am getting ready to replace all of the underlayment in a house that I am remodeling and would like to get other opinions on what material to use.
The house was built in the late 60’s. It is about 1600 sq. ft., has 4 bedrooms and 2 full baths. There is a 15’ x 15’ atrium in the center of the house which is open to the outside. There are 4 (6’ x 3’) windows per side. So a total of 16 windows around the center of the house. The floor joists are 2 x 10’s. I am not sure about the wood but it sure looks like cedar to me.
The original sub-floor is ½” plywood on top of which was installed a layer of 5/8” particle board as the underlayment. I have removed all of the particle board. A lot of it around the center of the house had been damaged (along with some of the ply sub-floor) over the years because the windows hadn’t been properly sealed.
I plan on putting tile in both bathrooms, a small kitchen and adjoining foyer. I will probably go with carpet in the rest of the house but laminate is still an option. Let’s just assume carpet for now.
I have some concerns with the transitions from tile to carpet which is one reason I am getting so caught up on the thickness of underlayment to use. I am getting ready to install tile in the master bath which is layered as follows: ½” ply sub-floor + ¾” ply underlayment + unmodified thinset + ¼” hardiebacker + modified thinset + approx. 0.3” tile = approx. 2”. I am using ¼ x 3/8 x ¼ notched trowel between hardiebacker and tile and ¼ x ¼ x 1/4 notched trowel under the hardiebacker. I plan on using the same layering of materials for the other bath, kitchen and foyer.
I plan on shimming the carpet at any threshold where it meets tile and want the carpet to butt to the tile with no transition piece. Will I have an issue with the height build up of the ply + thinset + hardiebacker + thinset + tile?
Right now I have 4 options in mind for the underlayment:
1) 5/8” ply
2) ¾” ply
3) 5/8” OSB
4) ¾” OSB
Here are some Pros and Cons of each:
5/8” Ply
Pros:
1) Will match original underlayment height so there should be less under cutting of door jams.
2) A bit easier to work.
3) Less weight on the floor joist. Not sure is this is even an issue.
Cons:
1) There will be a bigger height difference in the rooms which transition from tile to carpet (as opposed to using ¾” material) which I will have to make up somehow.
¾” Ply
Pros:
1) Makes for a stiffer floor.
2) I gain an extra 1/8” in height (as opposed to using 5/8” material) for areas which transition to tile.
Cons:
1) More weight on floor joists. Not sure if this is even an issue.
2) Will probably have to undercut door jams due to the added height.
3) A bit more difficult to maneuver around while installing.
OSB (5/8 or ¾)
Pros:
1) About ½ the cost of ply
Cons:
1) I have seen this debated before but since I have never used OSB I am a bit skeptical of the durability of this product.
I figured that I would need about 50 sheets of 4x8 material to complete the whole house. I will be shopping at Lowes since this is the most convenient place at the most reasonable price. The price difference between their Plytanium 23/32 x 4 x 8 Sturd-I-Floor T&G Plywood and Plytanium 19/32 x 4 x 8 Sturd-I-Floor Square Edge Plywood is about $1 so that’s not an issue. I would prefer a square edge 23/32 x 4 x 8 underlayment but Lowes doesn’t seem to carry that product.
OSB is about ½ the cost so the cost savings in about 50 sheets is around $500 so not a deal breaker either way for me. I would rather use plywood if it is the better product to use.
I am thinking that the 5/8” ply will be easier to install but for $1 more per sheet it seems crazy not to get a stronger product.
I know it would be better to have the thicker material on the bottom but since the ½” ply is under the walls I am kind of stuck with going with something similar to the original underlayment.
I would be really curious to hear what others would do in this situation. Have I left out any options? I plan on buying the material in quantities enough for a room or two at a time. Once I start purchasing and laying down the material, there will be no turning back.
Any feedback would be greatly appreciated!
-David
I am getting ready to replace all of the underlayment in a house that I am remodeling and would like to get other opinions on what material to use.
The house was built in the late 60’s. It is about 1600 sq. ft., has 4 bedrooms and 2 full baths. There is a 15’ x 15’ atrium in the center of the house which is open to the outside. There are 4 (6’ x 3’) windows per side. So a total of 16 windows around the center of the house. The floor joists are 2 x 10’s. I am not sure about the wood but it sure looks like cedar to me.
The original sub-floor is ½” plywood on top of which was installed a layer of 5/8” particle board as the underlayment. I have removed all of the particle board. A lot of it around the center of the house had been damaged (along with some of the ply sub-floor) over the years because the windows hadn’t been properly sealed.
I plan on putting tile in both bathrooms, a small kitchen and adjoining foyer. I will probably go with carpet in the rest of the house but laminate is still an option. Let’s just assume carpet for now.
I have some concerns with the transitions from tile to carpet which is one reason I am getting so caught up on the thickness of underlayment to use. I am getting ready to install tile in the master bath which is layered as follows: ½” ply sub-floor + ¾” ply underlayment + unmodified thinset + ¼” hardiebacker + modified thinset + approx. 0.3” tile = approx. 2”. I am using ¼ x 3/8 x ¼ notched trowel between hardiebacker and tile and ¼ x ¼ x 1/4 notched trowel under the hardiebacker. I plan on using the same layering of materials for the other bath, kitchen and foyer.
I plan on shimming the carpet at any threshold where it meets tile and want the carpet to butt to the tile with no transition piece. Will I have an issue with the height build up of the ply + thinset + hardiebacker + thinset + tile?
Right now I have 4 options in mind for the underlayment:
1) 5/8” ply
2) ¾” ply
3) 5/8” OSB
4) ¾” OSB
Here are some Pros and Cons of each:
5/8” Ply
Pros:
1) Will match original underlayment height so there should be less under cutting of door jams.
2) A bit easier to work.
3) Less weight on the floor joist. Not sure is this is even an issue.
Cons:
1) There will be a bigger height difference in the rooms which transition from tile to carpet (as opposed to using ¾” material) which I will have to make up somehow.
¾” Ply
Pros:
1) Makes for a stiffer floor.
2) I gain an extra 1/8” in height (as opposed to using 5/8” material) for areas which transition to tile.
Cons:
1) More weight on floor joists. Not sure if this is even an issue.
2) Will probably have to undercut door jams due to the added height.
3) A bit more difficult to maneuver around while installing.
OSB (5/8 or ¾)
Pros:
1) About ½ the cost of ply
Cons:
1) I have seen this debated before but since I have never used OSB I am a bit skeptical of the durability of this product.
I figured that I would need about 50 sheets of 4x8 material to complete the whole house. I will be shopping at Lowes since this is the most convenient place at the most reasonable price. The price difference between their Plytanium 23/32 x 4 x 8 Sturd-I-Floor T&G Plywood and Plytanium 19/32 x 4 x 8 Sturd-I-Floor Square Edge Plywood is about $1 so that’s not an issue. I would prefer a square edge 23/32 x 4 x 8 underlayment but Lowes doesn’t seem to carry that product.
OSB is about ½ the cost so the cost savings in about 50 sheets is around $500 so not a deal breaker either way for me. I would rather use plywood if it is the better product to use.
I am thinking that the 5/8” ply will be easier to install but for $1 more per sheet it seems crazy not to get a stronger product.
I know it would be better to have the thicker material on the bottom but since the ½” ply is under the walls I am kind of stuck with going with something similar to the original underlayment.
I would be really curious to hear what others would do in this situation. Have I left out any options? I plan on buying the material in quantities enough for a room or two at a time. Once I start purchasing and laying down the material, there will be no turning back.
Any feedback would be greatly appreciated!
-David