I’m installing a plain board, 1×8, #3 pine floor in a seasonal residence. The customer want’s it face nailed with square cut nails. It’s winter here and I’m laying the floor w/o heat. (interior temp 10-30 F.) How much space I should leave between the boards for seasonal expansion. The home is a summer residence for now but the customer wants to put in a woodstove later for year-round use. I stickered the flooring for 3 weeks in the fall.
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make it tight ---
Thank you for the input I'm nailing it tight and I hope the will be happy. ptimer.
Where are you? Is it cold and damp, or cold & dry?
If you're using squared edged #3 pine, I don't think you could possibly nail it too tightly, These folks must be looking for a very rustic look, sounds like they're going to get it<G> EliphIno!
I don't think it would work even as a subfloor. This place is going to washboard something awful! If the specs are for a finished thickness of 1" it may not cup too bad if you nail 1/3 in from each side, but I can't imagine it holding without screws. If you are worried about expansion in the summer that stuff better be sealed before it goes down too.
I ran into someone today, who did exactly what ptimer wants to do. It cupped, shrank, scratched and dented, and it was exactly what his clients wanted. Three years later and they are still thrilled with it. EliphIno!
gawd I wish I'd buy a digital camera
a"Attachment is the strongest block to realization"http://CLIFFORDRENOVATIONS.COM
Hi. I used that in my post and beam home and I think it is great. However I backprimed each board with thinned poly and there is no warp at all.( Real pain). That backprime is the key. I used thinned poly/oil finish topcoat buffed with 000 steel wool and wiped off.
Just leafing through older messages and came upon yours...I am installing random width pine, one batch for the second floor is 7/8" thick, the other batch is 1 3/8"for the first floor...they vary in width from 8" to 22". It is very dry, been sitting in my unfinished house for two years. There is no tongue and groove. We thought we would screw them to the floor joists, countersink the screws and plug with walnut plugs. We will probably put it down in the next month, it's a very cold winter here(NE Pennsylvania). I take it from other comments that I should butt them close together, and from you to seal the underside...any other suggestions?, as this is the first experience I've had with flooring...the floor joists are 2' O.C.
I also was going for a rustic look, don't mind some gapping, but I am worried about cupping with those really wide boards. Should I use felt paper underneath? Should I skip the felt paper and glue and screw? Any advice would be helpful, including the nailing pattern you think would work best...Thanks a bunch.
I'd be very hesitant to install any flooring over 6" wide, I get concerned with anything over 3+1/4". I think you're gonna get some serious joint cracks, no matter how you do it.
Have you considered making some relief cuts on the bottoms of the planks? That could help prevent cupping.
What type subfloor are you going over? Plywood? OSB? Can you fasten more often than 24" o.c.?
When you say "It is very dry, been sitting in my unfinished house for two years.", are you saying this is air dried lumber? Has it been through a kiln? Do you have a moisture meter? I don't think air dried lumber will get below lowest ambient moiture level, so depending on your local climate, it may, or may not be dry enough to install in a house that will have a controlled climate later.
The results could be disasterous with really wide boards like that.
Thanks for the response, it's going over plywood subfloor. It's not kiln dried, it was milled by an aquaintance of mine, stickered, and sitting in my uninsulated house. I apologize if this sounds uneducated but I'm new at this...when you say relief cuts do you mean straight cuts along the width of the underside of the board, or along the length, or a v-shaped cut? It's probably not as dry as it could be but I thought if it was too dry and we butted it tight it might swell and cup in the humid summers we have around here. I can live with gaps that are about a 1/4" or so but I wouldn't want them too much bigger than that, and I definitely wouldn't want them cupping more than that. My budget doesn't really allow me to change my mind at this point, I'll have to make the best of what I've got. If I'm going to get wide gaps then maybe I should forgo the felt paper as it would definetely show.
Thanks for your input, any other ideas?
I give it a shot - cupping is a problem when there is a moisture differential between the top an bottom of the board - if it's been stacked and stickered at location for two years, I wouldn't be much worried about moisture content - I would be concerned about creating a differential between the top and bottom of the board, and this situation is most likely to occur on the lower floor if the space underneath is not conditioned - tarpaper between the sub floor and planks would be indicated here - upstairs, maybe not, unless the heating/cooling system allows for signifigantly different temps/humidity between the level -
the 22" stuff is going to move app 3X the amount of the 8" stuff - might consider splitting the wide material in half to spread the movement into more spaces - it's hard to make a pleasing arrangement with material of such widely varying dimension anyway
8" to 11" boards, use three fasteners - in the middle and 1 1/4" in from either edge - 12" and wider, use 4 fasteners, 1 1/4" in from either edge, and the other two equidistant from the others - - frenchy has recommended screwing from underneath for a 'no fasteners' look - you might consider, perhaps he will pop in here with details -
If you face nail boards that are 22 inches wide you will get some severe splitting. The nail will want to stay while the board expands and shrinks..
A better approach if you have access to the bottom of the subfloor would be to go ahead and screw up from the bottom..
Drill holes 4 inches on center (from the top 'cause it's easier to drill down than up) make the holes ovesize, that is larger than the thread but smaller than the head. thus the screw can move back and forth while the board is shrinking and expanding according to how much moisture is in the air. have the screws long enough to go about a little more than 1/2 way into the planks when fuly snug. You will need to put the screws in from the bottom (I'd use deck screws, not sheetrock) If you are working alone set the first plank in place and go below to screw it in.. then put the second etc. go below and screw.. don't try to get everything in place and then screw the whole batch down..
This time of year here in Minnesota I'd put most of the needed gap in and then as the wood swells during the humid summer, the gaps will close up and not cup/ buckle. If the house will be airconditioned most of the year you can get by with much smaller gaps. but right now things are as dry as they get around here so I wouldn't butt them up tight!
I would definately use at least two layers of rosin paper unless there is a moisture differance between floors (another words are they both heated?) if there is a moisture differance, I'd be tempted to put plastic down and then rosin paper.
22 inch wide boards is a definate look. I personally love it, but those wide boards need special attention to keep from becoming a problem. To my mind the idea of 2 1/4 inch wide boards reminds me too much of a Gym or bowling alley. Any time you deviate from the tried and true extra effort needs to be taken..
Thanks for the replies from everyone...I like the idea of overdrilling the holes to allow for movement...what if we drilled from above, like you said, overdrilling the flooring...then switched to a smaller bit to continued drilling into the floor joists for a tighter fit there, countersunk the screws and plugged with walnut plugs (which I purchased some time ago). There is no ceiling on the first floor, the second floor joists show, as well as the plywood subflooring between...so I was hoping to drill the flooring into the joists, thus not exposing anything on the underside. If I did screw in from the bottom I could cover those screw heads, but I haven't yet given much thought to how to make that space between the floor joists visually attractive on a shoestring budget.
As far as the climate in the house, it's a cape cod over a finished block basement (which I have been living in for 2 years now). The basement is dry, is partially out of the ground on the south elevation, and has plenty of windows and a door. When the entire house (upper two floors) are finished there will be a central open staircase connecting all floors which will allow both winter heat (from woodstove in basement) and cool summer air to flow to each floor. I have planned for ceiling fans and skylights on the uppermost floor to help circulate and vent air. I also thought I should include cold air returns in the outside walls to keep air moving. This is a very old and simple method for heating and cooling, but the footprint of this house is small, 24 x 32' and I like living simply. The house is oriented to the south, I can take advantage of passive solar in the winter and it's in the woods, so I keep cool in the summer. Plus I hate to rely on the utility companies, especially in these uncertain days.
By the way, if I use felt paper and I get big gaps, won't it be more obvious cause the paper is black? Is there another alternative?
If I recall, your joists are 2 foot on center, so just screwing into the joists may not be enough..
you shouldn't have to drill into the subflooring at all! deck screws will self feed. Since the reason for larger holes is to accomidate swelling, as long as there is enough wood under the screw head to prevent pull thru you should be fine.
Making the subflooring look good from below on a shoestring budget means thinking outside the box and keeping you eyes open..
If you have acess to a planer, you might consider pallets.. Often available free you could take them apart and run thru the planner. Sheet rock is very cheap Or you could just paint the whole thing white..
I personally don't like felt in part for the reason you mentioned, rather I like to use rosin paper. But yes if you get gaps greater than the tongue of the board you will be able to see whatever is below.. Thus I prefer to lay flooring in late June.. No matter how tight I try to get flooring, there is always a little more room for the swelling of july and august and yet will open no more than the absolute minimum. Automatic spacing if you will...
(it won't work for commercial installers but works real neat for proper spacing for do-it yourselfers.)
Edited 2/19/2003 12:15:56 PM ET by frenchy
Thanks...I am taking a piece of flooring to the local paint store, they have a moisture meter, then I'll be a little more informed and I'll let you know.
PS. Thanks for your thoughts, and by the way, how much spacing would you recommend between boards for the anticipation of swelling?
There in lies the art of a floor..
the answer is far too complex for a simple pat answer.
Here are some of the factors that enter into it..
humidity swings.. from the dryness of winter heating season to the sweltering summer days.. how much variation? will the area be air conditioned? do you anticipate running a humidifier in the winter?
what sort of plants etc. will you keep in the area? (they add humidity in the winter)
how large is the house and how many peole will live in it.. (the more people the more humidity is added)
How wide are the boards? how many are 22 inches and how many will be 6?
orientation of growth rings and spacing of growth rings. (old growth pines with really tight growth rings expand less than second growth or plantation grown pines)
What is under the sub floor for example? If it's the basement and the basement is typical it may be fairly moist and you will need to deal with that..
You can shove the ends of the boards up tight if you want, however with various width boards you will need to have various width for spacing.. that tends to look sloppy unless you balance one width with another.. A more tidy approach would be to use the same end gap that you wind up using for the width gap.
For example you could use a 6 inch wide boards adjacent to the 22 inch followed by another 6 inch. you could then Cheat the spacing, use less than required with the 22 inch and more than required for the 6 inch and then the gaps would be somewhat more evan, while still allowing for the total movement..
Interesting subject, isn't it?
"the 22" stuff is going to move app 3X the amount of the 8" stuff - might consider splitting the wide material in half"
Split a 22" wide board?? That pains me! I think a better approach would be to decide which look you want:
1. rustic, "antique" - where there's just no substitute for the look of wide boards, but you're going to get gaps
2. more modern, less rustic - gaps minimized
If the choice is #2, save your wide boards for something else.
As others have mentioned, cupping is somewhat related to moisture level differential between the faces of a board. However, for any lumber that is not radially sawn (quartersawn), which is probably most of your pile, you can get some curvature when the moisture level changes, even if the moisture level is even throughout. This is what the relief cuts are intended to help.
Pete