Finish for cedar being used on screen porch

[Tina Mezera Kahl]

Hi there - I'm a total newbie at wood staining/finishing (beyond just basic deck staining). We are building a new house, and silly me, I offered to stain the cedar tongue and groove planks that will be used on the ceiling and walls of the porch - not realizing this would consist of 79 boards that are 14' in length. I also didn't realize I would be given a very short time frame to get this done (like, a few days). Yikes.

I live in WI, so the cedar/screen porch will be exposed to significant temp changes and humidity, but it will not be in any direct sunlight.

I went to SW, and they recommended BAC wipe-on stain. That went on beautifully, and that part of the project is done. For finishing, they recommended an oil-based fast-dry varnish. I applied one coat to a test board last night, and I hated the way it went on. It was sticky and uneven (despite my best efforts) and hard to apply. You can also see some overlap marks (again despite my best efforts). I'm now considering trying an aerosol spar urethane finish instead. It seems like that is better intended for outdoor use than this varnish, and I think the spray application would be faster. So, my first question is about what type of finish you'd recommend?

Second, a friend of mine who has done more staining than I have noticed that some of my boards were rough. (No, I didn't sand prior to staining - I took some advice from others who said they wouldn't bother sanding.) From what I've read, I think I should apply a coat of urethane then sand with 220 sandpaper? Is that right, or is there something else I should do at this point to smooth the boards without removing the stain or changing the color?

Any other advice for getting the best possible results at this point in the process would be appreciated. I'm learning a lot as I go, but I don't plan to ever do a project like this again, so my goal right now is to finish the boards properly and get it done with as quickly as possible. Thank you!

[Chestnut]

Buy a cheap HVLP sprayer or rent one if possible. One of the all in 1 units like this. or this one might be better. Another option is a compressor HVLP but  that comes with it's own can of worms and complications like needing a good compressor to run the gun and dealing with oil and water from the compressor contaminating your finish.

Buy some exterior rated water based poly like General finishes Exterior 450 and spray them. You'll be able to spray that in minutes vs hours of brushing. Sand between coats.

Exterior 450 can be applied with a brush as well but the $100 spent on that HVLP will pay for it's self in 1 coat.

That's how i'd do it.

[Pondhockey]

5 hours ago, Chestnut said:

Buy a cheap HVLP sprayer or rent one if possible. One of the all in 1 units like this. or this one might be better. Another option is a compressor HVLP but  that comes with it's own can of worms and complications like needing a good compressor to run the gun and dealing with oil and water from the compressor contaminating your finish.

Buy some exterior rated water based poly like General finishes Exterior 450 and spray them. You'll be able to spray that in minutes vs hours of brushing. Sand between coats.

Exterior 450 can be applied with a brush as well but the $100 spent on that HVLP will pay for it's self in 1 coat.

That's how i'd do it.

I think that 'nut's approach is very reasonable, but remember that you will want to mask those areas (windows, doors, sills, hardware...) that you don't want sprayed and you might be pretty sorry if you don't.

[edit: if you are treating the boards before they are installed, then go for it!]

[Chestnut]

11 hours ago, Pondhockey said:

I think that 'nut's approach is very reasonable, but remember that you will want to mask those areas (windows, doors, sills, hardware...) that you don't want sprayed and you might be pretty sorry if you don't.

[edit: if you are treating the boards before they are installed, then go for it!]

I had a serious thought as to suggesting taping and putting plastic on everything off and spraying in place. I figured doing it in place was more work on the prep than it's worth.

Also if you have a power sander with variable speed you could put some 320 on that and use it to sand the first coat of finish. It might make things a bit faster. With the power sander you'll want to move faster than you do on bare wood so you don't sand through.

[drzaius]

Am I crazy for suggesting that this just be done with an exterior semi-transparent fence/deck stain? One coat, brushed or sprayed & your done. And you don't even have to be that careful with the application. And being out of the sun & rain, it'll last many years before needing recoating. Super easy, fast and cheap. This isn't fine furniture here.

[wdwerker]

I'm with Frank.  Exterior stain can be rolled on to apply it quickly then brushed to get it smooth & cover edges & missed spots. 

[drzaius]

For that amount, maybe not even worth getting out the spray equipment. Roller & brush as Steve suggested.

[Chestnut]

I don't think he's coming back to see the suggestions. I saw that he wanted it smoothed some, i don't know if apply a deck stain and sanding smooth would work but with a film finish you could sand it back a bit and it'd smooth things somewhat.

for 1,106 lin ft I'll bust out spray equipment. If it's over 100 lin ft I'll bust out sprat equipment, this is considering a water base clear though. I don't really deal with deck stains ever don't really plan to.