Float deck on Deck Blocks in the Northeast?
Year into owning our house we are discovering more and more that placing deck furniture on grass is not sustainable practice. So I am looking to build something that covers 12X16 area and isn’t much taller off the ground than say 6″-12″. Definitely not attaching it to the house or I am going to be in permit territory, which makes the taxman very happy in my town.
I considered pouring cement slab, but prospect of mixing 100 80# bags of cement and, however handy I may be, fear of it setting before I have finished it, keeps me away from that solution. Dealing with cement companies here is a pain (at least ones I know of), since I am not a contractor.
So solution I came across is floating deck system using Deck Blocks. You set those in 4′ grid pattern and supposedly even in frost heave territory i should be OK (I am in MA).
Here are three questions:
1. Seems like kiln-dried cedar boards are only about $100 more for my project (looking at Home Depot pricing) than treated pine. Is it worth going cedar, or should I stick with treaded pine? Since it is kiln-dried, I assume 0.25″ gap between rows is the right gap?
2. 16″ OC or 24″ OC. I can’t seem to fit consistent answer on that for floating decks.
3. Do you stain right away treated wood (if that is the route to go) so deck could be used or do I have to wait until wood dries at least a bit?
Any other advice?
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Replies
Your proposed plan may be more complicated and expensive than is necessary.
Several years ago, we put an addition on our house. To do so, we needed to remove a deck. Rather than trash it, we disconnected it from the house and put it out in the yard, on 4" thick solid concrete blocks every four feet or so around the perimeter. No footings or anything else. The deck is about 10 x 16. If the frost heaved it, we didn't notice. Unlike a house, a little movement doesn't matter, as there is nothing to crack or break on a deck. We're in Maine.
Deck was framed with 2x6 PT lumber, with 5/4 cedar planks for decking. The decking lasted a good 15-16 years before it got punky. No finish was ever applied.
All you need is a level spot and a weekend, a few friends and some beer.
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Apollo,
I build decks at grade much as Stephen recommends. Level out the grade on which it will sit. Fill with several inches of compacted clear crushed gravel. Frame the deck with PT 2"x4"s that will bear along their entire length on the gravel, and deck with whatever product you like. The options range from cedar to concrete pavers.
I just don't see 2X4s surviving the abuse and being that close to the soil. Wind lift is a concern too.
Apollo,
That's why you use pressure treated lumber, and separate the structure from the soil with well drained gravel.
No wood deck built on grade is at any risk to wind lift. One built on pier blocks might be.