Our basement boiler-room (steam-heat, water-heater, other heater, all gas) has, up high, a window looking out into a grate-covered pit. (Grate at ground-level.)
For safety from CO, we keep the window open a few inches, always, allowing boiler-updraft to drag in fresh air.
Problem: leaves (southern Westchester county) and then snow, potentially 100% covering the grate, dangerously.
What to put over the grate to keep leaves and snow away from it.
Used to have ugly office-chair rug-protector draped over it. Recently the boss (of this house) tossed it out, calling it UGLY. (Well, yes, it was -- but it added safety.)
Happens that six months ago I (surrepticiously) retrieved from our garbage some old half-inch pieces of plywood.
My idea is to use one of them to lay one of them across near-grate concrete-blocks, to return the room to a "safe" condition.
To avoid instant UGLY!-judgement, maybe painting it dark-green would help.
QUESTION: how to weatherproof it?
What kind of paint, primer, brands, number of coats, etc?
THANKS!
David