I am going to install panels on the ceiling in the basement and a panel on the basement door. What type of panels are best to use? It is often humid in the basement. Is there any difference in moisture resistance for, for example, construction plywood, OSB boards, chipboard, and MDF boards? I am also considering the difference in usage areas for construction plywood versus OSB boards?
What function should the boards have?
If it is so humid in the basement that you need to choose the board material based on this, I think it would be wise to address the moisture problem instead of buying moisture-resistant boards......?
If it is so humid in the basement that you need to choose the board material based on this, I think it would be wise to address the moisture problem instead of buying moisture-resistant boards......?
I agree with MathiasS. If you have a major moisture problem, it might be better to fix that first. But if I'm going to try to answer your question, none of the boards you mention are particularly moisture-resistant. MDF and particle board are the worst, followed by OSB and construction plywood. However, there is construction plywood for outdoor use that is more moisture-resistant. What function should the boards have? Should they sit under the subfloor and support insulation? Or keep people out? Or what?
The boards in the basement ceiling support the insulation. As for the basement door, I have insulated it because the temperature difference outside and in the basement causes condensation on the door. The board should sit over the insulation. I have taken measures to reduce the moisture, but I still want to choose something that provides a little margin without large costs.
Plyfa is good, but it is still wood, and if it is damp as you describe, there is a high risk that mold will grow on the boards.
Fiber cement boards are more moisture resistant, but they too can probably get mold growth if it's too damp for long periods.
Fiber cement boards are more moisture resistant, but they too can probably get mold growth if it's too damp for long periods.
Is there any difference between OSB boards and regular construction plywood in terms of moisture resistance? Since the appearance does not matter much in the basement, I was considering installing OSB boards and painting with silicate paint intended for wood. Silicate paint releases any moisture and is also antiseptic.
Maybe plywood is better? One states that it is intended for outdoor use. Then you should have a good margin for installation in the basement ceiling.
I found 9 mm grooved plywood where it says it is intended for outdoor use with waterproof WBP glue.
http://www.jemfix.se/plywood__11566/spaarad-plywood_9000218
Here is 12mm P30 plywood with waterproof WBP glue. It doesn't say if it also works outdoors.
http://www.jemfix.se/plywood__11566/konstruktionsplywood_9029981
Byggmax P30 plywood. It doesn't say anything about waterproof glue or if it can also be used outdoors.
https://www.byggmax.se/skivmaterial/byggskivor/plywood-och-osb/konstruktionsplywood-p30-p1005
What's the best option to choose? Or is it enough with OSB panels? I live close to Byggmax, so that would be easiest.
I found 9 mm grooved plywood where it says it is intended for outdoor use with waterproof WBP glue.
http://www.jemfix.se/plywood__11566/spaarad-plywood_9000218
Here is 12mm P30 plywood with waterproof WBP glue. It doesn't say if it also works outdoors.
http://www.jemfix.se/plywood__11566/konstruktionsplywood_9029981
Byggmax P30 plywood. It doesn't say anything about waterproof glue or if it can also be used outdoors.
https://www.byggmax.se/skivmaterial/byggskivor/plywood-och-osb/konstruktionsplywood-p30-p1005
What's the best option to choose? Or is it enough with OSB panels? I live close to Byggmax, so that would be easiest.
I read somewhere that the boards should be mounted with a couple of mm between them due to movement in the wood. Is it necessary? It looks a bit better without gaps. The temperature in the basement usually ranges between zero and plus 18 degrees.
It's probably neither here nor there which glue they used. It could mean that the boards start to delaminate at the edges, but only after many years. If you have such high humidity that it occurs, you'll probably have mold problems long before that. However, boards intended for outdoor use are, of course, the safest option.
OSB might also work.
Variation in humidity throughout the year dictates how the boards/wood shrink/swell. You should definitely leave a few centimeters of expansion gap at all edges against the floor/wall/ceiling. Wood can crack walls and plaster. If you don't leave any gaps between the boards, you should then fasten them tightly with nails/screws because they will want to warp since they cannot expand sideways.
If you let the boards sit for 1-2 months in the basement (stacked with spaces between them) when it's most humid, you minimize the risk of them swelling, as they will have acclimated to the humidity.
OSB might also work.
Variation in humidity throughout the year dictates how the boards/wood shrink/swell. You should definitely leave a few centimeters of expansion gap at all edges against the floor/wall/ceiling. Wood can crack walls and plaster. If you don't leave any gaps between the boards, you should then fasten them tightly with nails/screws because they will want to warp since they cannot expand sideways.
If you let the boards sit for 1-2 months in the basement (stacked with spaces between them) when it's most humid, you minimize the risk of them swelling, as they will have acclimated to the humidity.
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Thank you for the good response. I have now also learned that there is a difference between building plywood and construction plywood. Construction plywood has higher quality with more durable glue. It was mentioned somewhere that OSB boards are an intermediate between plywood and particle boards. But maybe OSB will suffice since the boards are to be painted? Plywood costs twice as much as OSB, so I have to try to choose what is sufficiently good.
Here I found some information about plywood.
http://www.moelven.com/PageFiles/311157/V_nerplyP30_Konstruktionsplywood_Rek_201509.pdf
Here I found some information about plywood.
http://www.moelven.com/PageFiles/311157/V_nerplyP30_Konstruktionsplywood_Rek_201509.pdf
If appearance doesn't matter, then it doesn't matter which board you use from a moisture perspective. If it's so humid that there's a problem with any of the boards, you will have enormous issues with mold anyway, so the boards will be your least concern. Therefore, choose the cheapest one.