Pine Stripwood for Exterior Use

[cwcw]

Due to warping to some of the joists used for my deck frame, I've realised that about 4 joists need raising for the boards to continue the gradual slope for drainage. Currently the boards that are down so far gather water around these joists because the slope goes down to them but then the warp joists raise the incline again.

The frame is all built, very strong and with lots of feet so I've figured the easiest solution is to build up these joists so the boards are raised and continue the incline to drain off, rather than puddle there. I would need to raise them by 4mm to 1cm each and I was thinking I could use pine stripwood for this.

As it's for interior use, would it be ok to use outdoors if I soaked the pieces in wood preservative first? Or is there anything that would be better to use and still similarly cheap?

Also, I am assuming it is worth the effort to correct this now - how much damage do temporary puddles cause to the decking boards?

 

[TheVictorian]

I'd grab a set of plastic packers and use those I think, a pack will contain sizes from 1mm thick to 6mm and they would perhaps enable you to get the slope you need a bit easier?

 

[cwcw]

That sounds like a good idea, thanks. Rot would not be a worry but what about driving the screws through them? Where do they sell them?

 

[TheVictorian]

Something like
http://bit.ly/18Jd1Sj

 

[cwcw]

I bought a big box of plastic packers from eBay and used them on some of the joists. I actually used on more joists than just the warped ones in order to achieve the gradual slope I wanted and they did allow 1mm precision. I glued them to the joists and then taped them with masking tape to stop them slipping as I drove the screws through. The boards feel much more solid now as they touch every joist properly (albeit via the packers sometimes!) and also the puddles no longer form. Excellent tip, thank you.