Lid for coal bunker

[macbrains]

Hoping for some ideas....

I have a large external coal bunker, approximately 8 feet by 4 feet. The lid has always been made of plywood, and the previous one lasted ages until it finally needed replacing. I bought some more "external" plywood about a year ago, had it cut into manageable sections and treated it with "Fencelife" (or similar, can't remember). Sadly, it lasted only about 9 months before it started to open at the edges and has now fallen to pieces...

Has anyone any thoughts on what I should replace it with? Someone told me that most plywood now comes from China and - as is my experience - does not last. I assume there are various grades of external plywood - what should I be looking for? What to treat it with?

Or is there another product I could use? It needs to look reasonable as it's just outside the kitchen window.

Many thanks in advance for any thoughts or suggestions.
Rob

[Slarti]

Hoping for some ideas....

I have a large external coal bunker, approximately 8 feet by 4 feet. The lid has always been made of plywood, and the previous one lasted ages until it finally needed replacing. I bought some more "external" plywood about a year ago, had it cut into manageable sections and treated it with "Fencelife" (or similar, can't remember). Sadly, it lasted only about 9 months before it started to open at the edges and has now fallen to pieces...

Has anyone any thoughts on what I should replace it with? Someone told me that most plywood now comes from China and - as is my experience - does not last. I assume there are various grades of external plywood - what should I be looking for? What to treat it with?

Or is there another product I could use? It needs to look reasonable as it's just outside the kitchen window.

Many thanks in advance for any thoughts or suggestions.
Rob

For external use I'd suggest marine ply. If it is good enough to build boats with, it should last in your environment.
Also marine paint. More expensive but very tough.

Alternately, plastic sheets like https://www.sheetplastics.co.uk/

Slarti

[JohnB]

I knocked one up from some featherboard fence panels (that my dad bought in the 1950s!) Pressure treated, they should last for ages provided you have a slope to throw off the water.

[macbrains]

Many thanks both. Having researched "marine ply" it seems there are many types/grades etc, some of which say they should not be used for boatbuilding!

[richlist]

Shed roofs seem to last for many years. So why not use the same method.......cheap sheet material then cover with roofing felt or overlapping felt shingles.

[twotwo22]

You can buy marine ply, but many builders merchants stock WBP and sell it as marine ply.
Have a read here.. http://www.robbins.co.uk/marine/sheet_materials.asp

[bungeejumper]

Stating the obvious here, but if you're using ply, pay special attention to how you seal it, especially at the vulnerable sawn edges. As suggested, there's nothing tougher than marine paint - if it were me I'd also think about applying something like resin to the edges before the paint went on.

I've had less success with yacht varnish, though. In outdoor applications, even the expensive stuff only seems to stand the weather for three or four years before the rain gets in. And that's on a hardwood base!

Returning to topic, I see that you can buy tantalised plywood. http://www.molevalleyfarmers.com/mvf/st ... -x-2440mm., or https://www.southern-timber.co.uk/produ ... eated-ply/. No idea if it's any good, but it would seem like a good idea.

BJ

[bungeejumper]

Returning to topic, I see that you can buy tantalised plywood.

LOL, curse that auto-correction.

BJ

[JohnB]

We had wood covered in shed felt on our bunkers for decades