[John_F]

Hi all,
I'm getting ready to build a small deck and after looking over some of the threads here, I figured I'd ask for help before I'm in over my head. The deck will be bordered on 3 sides by concrete (house, wall and steps). The steps are 4' wide, so there is an 8' wide section for 8' and then it becomes 12' wide, after it clears the steps, for another 8'. It's all on one level. We plan on using Trex, although after seeing some of the threads I'm a little leary. I live on the dry side of Wash. state so hopefully mold isn't an issue. My wife wants a hot tub on the 8 ft. wide section. I figured I'd center the joists in that part at 12" and the other half at 16". My biggest problem is ground clearance. The steps were formed in such a way that I'm limited to 2x4 joists. The caliche (sp) makes digging down for footings almost impossible. Using a roto-hammer I think I can make enough of a hole to concrete in some of the brackets that are on top of pier blocks (not sure of their name). I was thinking of attaching ledger boards on all the concrete surfaces and running a 4x4 beam across the front of the stairs over to the house and using a joist hanger to attach it to the ledger board on the house. Because of the height limitations I was wondering if I could either use 4x4's for joists or double up 2x4's.
I just read back over this and it seems clear as mud, so if you can make heads or tails from the description I would appreciate any help you care to give. This group seems to have a lot of good info in the threads I read.
Thanks in advance,
John

 

[Willie T]

Sorry, I'm not visualizing this one. But one question.... 2 x 4 joists? To support a hot tub?

 

[jaros bros.]

Ummm....2x4s or 4x4s. Hmmmm...you need to do some serious load calculations.

 

[johnnyboy]

http://www.decks.com/Calculators/JoistSpan.aspx

calculator for basic load/joist spacing NOT INCLUDING THE HOT TUB weight.

i.e. a pine 2x6 will span just under 10' @16" o.c.


What is the measurement from ground to stairs? I have small 10x20 deck built "floating" on skids, 2x6 joists on three 4x6" beams, rock solid. Not attached to the house and set off a few inches for frost heave reasons.

I don't see how you could get much lower to the ground than that without sacraficing strengh/safety. What about a ramp/step up?

You could use a million of those concrete deck support blocks but I still don't think 2x4 joists would feel solid enough.

 

[johnny67]

John, check out this web site for deck ideas. I built one and put a hot tub on it. It is built with all treated 2x6's it can go as low as 13" in height. http://www.deckplans.com/adding-a-hot-tub

 

[Willie T]

John, check out this web site for deck ideas. I built one and put a hot tub on it. It is built with all treated 2x6's it can go as low as 13" in height. http://www.deckplans.com/adding-a-hot-tub

Wow! Tons of support. Cool! :thumbsup:

 

[Scuba_Dave]

If you are using PT 2x4 studs on top of the cement (direct support) that would work

A picture is worth a thousand words
That would help people see what you are working with/around

 

[John_F]

I don't have a site picture as yet, but here is what I've got drawn up so far. I know the 2x4 issue is a problem. I was hoping that I could beef it up enough by cross bracing the fool out of it. I'll post a picture as soon as I can.
Thanks in advance

 

[Gary in WA]

So a slab under hot tub won't work? With composite you need an air space or it will mold. 8" on some, read the fine print.
Be safe, G

 

[John_F]

I hate it when I get too long to think about a project. What if (famous last words), I make the deck a 2 level affair. I'm sort of limited on the height of the large (8'x12') section, but I could raise the smaller section (where the wife wants a hot tub) to allow for real size joists. It would be bordered on 3 sides by concrete so I could attach anchors for a rim joist. Am I at least on the right track?
Thanks

 

[Gary in WA]

A lot of decks are built half-way up the hot tub, only sticking out 6-18". Are you putting the deck and tub at the same level?
Be safe, G

 

[John_F]

Thanks for the reply GBAR. Unfortunately the hot tub (if and when we get one) will need to sit on the deck.
I've been wracking my brain over the lack of strength in this thing. It woke me at 3AM. I got to thinking what if I raise most of the deck up to the height of the 1st step of the stairs (about 8-1/2"). This would let me use 2x6 joists instead. There needs to be a 3-1/2" x 12' section next to the patio that is lower, but the rest could step up.
The original picture shows 1 "beam" in the middle of the shape. In order to raise the piece between the stairs and the patio, I would think a 2nd one is in order and I'm wondering if a 3rd one in the top right section would add strength. I'm think that if I can use 2x6's on 12" centers than maybe it could be strong enough. Would it be better to add a 3rd beam and hang the joists off of it with hangers or run 8' long joists and set brackets in concrete to suppport it?
Thanks a bunch for your help.
John

 

[Willie T]

You really can't dig a three foot hole, pour a slab down there, and install the hot tub... building the deck around it?

 

[John_F]

Hi Willie,
We broke a back hoe trying to lowere the area a couple of inches.and it's a little too close to the house for dynamite. We always joke that we live on a rock. The hot tub is down the road a bit also. I thought about pouring a pad but then there would be a hole in the deck waiting for something to put in it. The tub might not show up for years at this rate, but eventually that's where she wants it. I'm just labor on this project
Thanks for the help.