exterior finish for recycled pallets

[Chippyinexile]

Buenos dias from Spain!
I've just made the first of several feral cat shelters to be placed around my local village. They are made from recycled pallets that I whizzed through my thicknesser on one side to give a relatively smooth finish.
The roof bit is OSB covered in roofing felt. I plan to put them on some bricks to keep them off the floor.
My question is, can anyone recommend a way of finishing the pallet side cladding? Obviously it's very sunny here but we do get significant rainfall at times too. I'd like to keep the 'natural' pine look so was thinking along the lines of possibly some kind of oil? Maybe linseed? Teak? Some kind of proprietary decking /outside furniture finish?? I once used varnish on an exterior table and it blistered badly so am not keen on using that but I'm happy to be advised otherwise.
Thanks in advance for any advice!
Cheers, Anthony

 

[eribaMotters]

Are you trying to keep them looking "new" or do you want to preserve them from rotting.
I think in the first case any finish [sits on the surface] you put on will get hammered by the sun and need re-doing at least every year.
If the second and you apply a clear preservative [soaks into the wood] this will last a few years before you need to give it another coat. Ideally it will be totally clear so allowing the wood to go grey with age. It would be my choice.
I'd try the big DIY sheds to see what they sell.

Colin

 

[Agent_zed]

I realise you want to keep the natural look but one option for a technically natural look is Shou Sugi Ban (wood charring) although admittedly not the light coloured pine you might be after. If you aren't already aware heavily charring the wood helps to preserve it.

I did a lighter touch with a blowtorch to bring out the grain on some wooden christmas ornaments and it looks really good. Makes the grain show really well. Although this alone wouldn't prevent decay.

As above I'd stick some clear preservative or danish oil on it too.

 

[Fitzroy]

A very different environment to the UK, but the best thing for longevity is to keep the timber dry, or ensure it can dryout when it gets wet. Don't sit directly on the earth/soil, or too close to a wall where it will remain damp. Regards finish, oil will look ok for a few years, rubbish varnish will be dead in a year, decent varnish with multi coats can last 3-5yrs. Intense sun will destroy any finish, so avoid hotspots/sun traps. Deteriorated finish looks worse than no finish, if you decide to finish them either be ready to refinish periodically, or accept they will look good for a few years, rubbish for a few years, and then naturally aged after that.

My opinion is select decent dry, not to sunny locations, and leave them unfinished to silver over time.

 

[recipio]

I would avoid any solvent based finish - they take weeks to dry properly and cats hate the smell. Something like a water based exterior stain with UV protection might be your best bet. I know from experience that clear finishes don't last a fraction of the pigmented type. That means changing the colour of the wood unfortunately.

 

[Chippyinexile]

Thanks to all for your suggestions.
I’ll have a hunt around DIY sheds for some products. I must say the idea of charring the wood is intriguing, I didn’t even know that was a thing! I will further investigate this and try it out on some off cuts, funnily enough I had to invest in a new blowtorch to stick the roofing felt down.
I’ll certainly try to find sheltered spots to locate them to give whatever finish I choose the best chance of lasting a while.
Thanks again.

 

[Shan]

Thanks to all for your suggestions.
I’ll have a hunt around DIY sheds for some products. I must say the idea of charring the wood is intriguing, I didn’t even know that was a thing! I will further investigate this and try it out on some off cuts, funnily enough I had to invest in a new blowtorch to stick the roofing felt down.
I’ll certainly try to find sheltered spots to locate them to give whatever finish I choose the best chance of lasting a while.
Thanks again.

Bom dia! I'm living in Portugal and when I came here I put up some shelves made from pallets. I imagine that the climate is similar but we get a lot of rain here specially in winter. They have been in place over 10 years and have held up pretty well considering that I didn't put any finish on them. I might be wrong but I thought that it is treated wood which they use in pallets??
As to the burning suggestion above shou sugi ban, it's a good idea. The Japanese have been doing it for a long time and especially on houses that were isolated and at risk of fires it prevented them from burning down. Also termite proof so will last year's. I've made a couple of bowls using the technique. I'll include a couple of photos. Just excuse the state of the wall.
But I'm sure what ever you do that the cat's will be pleased to have a place to kip!

 

[Chippyinexile]

The bowl looks stunning Shan, really nice.
As I mentioned, I’d never heard of the charring technique before but the more I research it, the more I’m drawn to it.
I think I may give it a go with at least one of the shelters.
Cheers.

 

[TheUnicorn]

would burnt wood not be an offputting smell for sensitive noses (cats)? maybe it would air off fairly quickly