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Building a deck on solid rock

24K views 3 replies 2 participants last post by  Scuba_Dave 
#1 ·
I'm planning to build a wooden deck near a river, problem is that the entire ground is solid rock & its sloped too ( 15 degrees approx). Not sure how to attach my foundation/posts on top of solid rock.
Deck size approx 15' x 25'. Ground level. May tie a boat to it in the future.
Possible ideas:
Rent/buy a rotory SDS hammer drill, drill 1 1/2" hole, about 12" deep, insert 1" diameter stainless steel bolt, (maybe 8” long) then secure bolt in hole with concrete or epoxy. Attach a Simpson 4x4 connector to the bolt & then attach my beam/post to it. With the ground being rock, its unevenness concerns me with this approach, ie... the Simpson adapter would probably not sit flat on the rock.
Or…
Rent/buy a rotory SDS hammer drill, drill a series of 1 1/2" holes, in close proximity, about 12" deep, then use another SDS bit to break the away the rock. Fill hole with cement. Rinse & Repeat for each post.
I've never worked with an SDS hammer drill nor have I ever drilled rock. Can the above methods cause the rock to split/fracture, in return making my foundation weaker??

I'm out of ideas. Any suggestions, info, or links are greatly appreciated.
 
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#4 ·
Stand alone is better since you do not have to worry about frost
Of course if the rock is like that it probably won't move
I'd be inclined to drill & use simpson connector
If the connector is lined up right, cut the bottom of the post to match the slope

I'm not sure of the appropriate method for bolting into the rock

For the boat I think I'd tend to drill some other holes & put some separate anchors in
 
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