Greenhouses, Sheds and Sun Rooms - gravel bed for a slab foundation

Hi all,

Can anybody tell me what type of gravel I should use for laying down a bed on which a slab will eventually sit? I know I'll have to tamper it down, but what size and type is best for good drainage?

Thanks in advance.

Pea gravel, or anything small like that works well. Don't tamp it -- just lay the base in, skreed it out level and pour the concrete on it. What I do is set the forms for the concrete first and use those as my level line for skreeding the base. Assuming that your slab will be 3-1/2" thick, tack 2 stakes on the top of a 2X4 and let the stakes ride on the forms. That will skreed the base 3-1/2" below the top of what the slab will be.

I did exactly what you said and it worked out perfectly. Forms are down and ready for the pour. You da man.