Deck Materials

[Pappy]

I am in the process of putting up an above ground pool. The 'pad' is ready and the pool will go up today. Other than the obvious enjoyment and relaxation it allow the wife a way to exercise.

To make access easier for her I am going to build a 5x8 deck. Deck building is a new endeavor for me.

Drawings were done with Lowe's Deck Designer and did not give me the flexibility to incorporate changes to the framework that I want. The program's cost estimate is $1050 - $1104 but I think I can bring it in for far less.

Basic Design. I plan to move the outside posts to the corners, use 4x4x8' so they will also become part of the rails. The inside posts will be positioned as close to the side of the pool as practical and still avoid any contact form the flex of the sides. The program would not allow the steps to be drawn less than 3' but they will be 2' 6" so she can easily hold on to both rail caps.



The second pic is a parts diagram that comes up in the printout and is included to make sure the same terminology is used by everyone.



Known cost savings. (I clicked on the treated wood option for all the wood components and some high cost baluster materials just to speed up the design process.)

1. I have access to some Trex decking that has some tar on it that I can get for 50% of retail. I used some for the edge of the pad' area and Goo Gone cleans the tar of with a little elbow grease. I will cut the planks to length and task her with that while I build the framework.

2. Balusters will be made from 1/2" conduit at >$1.50 for a 10' stick. (I already have a modified spade bit as recommended by Loring from building my wood rack).

3. Use SPF (a.k.a. Whitewood) for the handrails and framework components that are not in contact with the ground. The only thing I don't like about this is having the treated 4x4 extending up to be part of the rail supports is going to cause stain match problems.

4. Use Portland cement and 'mix my own' for the post footers and contact pads at the bottom of the stair stringers. I have a mixer and enough sand and gravel left over from a past project.

Questions.

Would using one of these allow me to safely use untreated 4x4 for the posts?

http://www.lowes.com/pd_15897-71255-17004_0__?productId=3014602&Ntt=post+harware&pl=1&currentURL=%3FNtt%3Dpost%2Bharware&facetInfo=

http://www.lowes.com/ProductDisplay?partNumber=58588-166-CPB44&langId=-1&storeId=10151&productId=3367966&catalogId=10051&cmRelshp=req&rel=nofollow&cId=PDIO1

Any graceful way to end joint treated and nontreated 4x4's so the posts above the deck would match the material in the rails and still provide treated contact at the ground. Possibly a tenon in the treated part to a mortise in the non treated positioned so the beam would screw to both sides of the joint to add strength? The same idea could be applied to the stair stringers.

Any other cost cutting ideas or caveats I need to watch for?

[mineengineer]

Just an FYI on Trex Spans

If your using the 5/4 trex deck boards you can go 16inches on center for the regular deck joists, but you can only go 10.5 inches on center for the stair stringers. More info here if you havent already seen it:

http://www.trexpartners.com/usage-and-care/usage-guidelines

Link

[frumper64]

Don, I know you are trying to keep the costs down, but I would think long and hard before using untreated wood instead of treated for the handrails and pieces not in contact iwth the ground. I don't think using treated would cost all that much more and it would certainly last a lot longer and, I believe, would also be safer for your wife if she is relying on the handrails. You do have to wait a while before painting or staining treated lumber to be sure it is dry enough to take the paint well. Otherwise, you will soon be repainting it.

Jim

[JR]

You've got a great start on this project, Pappy.

I like the use of Trex for the decking - especially when found at a discount! You should have a lot less trouble keeping it in good shape down the road. It does have different requirements as to joist spacing, as noted by mineengineer, so play close attention to that.

I would think about using an opaque stain or paint. That way you won't have any trouble matching its effect on different materials. It also means that when you have to fill cracks or splits there won't be any trouble covering the repair. I'd also think about having some sort of skirt around the base of the deck, mitigating the problem of difference in materials, but also masking any construction details with the post bases or whatever. You could also gain some storage space for pool tools, chemicals, etc.

Most deck designs have beams attached to the top of posts, then rail posts attached to the rim joists. Attaching the beams to the sides of the posts requires special considerations, about which I can't offer advice. If you want to go this route, and you want to use the two-materials approach to posts, a scarf joint is the proper connection between the two materials. A simple half-lap scarf would be plenty good enough.

I recommend using PT for the posts, no matter which connector you choose. In fact, I'd recommend using the 1" offset bracket along with PT. Posts do rot at the bottom, so you should do everyting you can to mitigate this. Then again, maybe my recent experiences are coloring my thinking.

Here's the deal with post connectors. If you use treated wood you can attach directly to concrete. If you use untreated wood you need a connector with a 1" standoff. In either case an H-bracket is the proper connector.

Check out the Simpson Strong-Tie Deck Center site for lots of good information on connectors for this application. These guys have done a great job of getting their products incorporated into building regulations, so following their advice is a good idea.

Here's a little pdf from my town's site giving some good ideas on what one needs to do for a conformant design.

The balusters need to be no more than 4" apart. Getting them spaced evenly is a problem. Here is a video with a really nifty trick from Tom Silva on doing this.

One final thought. Make sure the pool equipment is oriented such that you have good access to everything. You may eventually have to repair leaks, motor, pump, etc. And of course the filter needs cleaning periodically.

HTH,

[JimD]

I would also use pressure treated for all the structural pieces including the handrail. It will last a long time with no stain but look better with stain, I suppose. For my exposed deck and stairs, I used trex for the flooring and PT for the framing and handrails. I used painted electrical conduit for the spindles. I used cheap spray paint to paint the conduit white. It held up 5 years or so but is peeling in spots now. I used plated fasteners on the trex and some of them are rusting. The trex gets hot in the sun and the fasteners get extra hot. If I was doing it again, I would investigate other fasteners. I believe the nice pocket hole company makes a jig that simplifies edge screwing decking and I've seen other fasteners. Stainless steel screws would probably hold up better. For the base, I would either just put the PT in the ground with some concrete around it or poor a little concrete footer and use a J-bolt and galvanized base. I did the latter on a beam for my son's deck. The "builder" just had posts in the ground without concrete or anything. Anything you do is going to be better than what some people get by with. But a simple hole in the ground, J-bolt, and galvanized base will not add much cost and will keep your deck solid. I got the idea I used for the spindles from Fine Homebuilding. I drilled an extra deep hole in the handrail (2x4 on edge) and put a dowel on the bottom rail. To install I went up the deep hole and then down over the dowel. Worked fine.

Jim

[Pappy]

Part of the reasoning for less treated wood was less for costs but more from experience with splinters. I know the chemicals in PT wood are different and safer now but pine does tend to splinter more than some of the straighter grained woods available. I may still go with Douglas Fir for the top rail for this reason.

Reading through some of the responses I am also leaning more toward paint over stain for the wood components. A large part of that decision is that the filter/pump system is going to be under the deck and, while I don't want it enclosed, I am thinking of using colored plastic lattice panels to keep critters (Especially the 2 legged ones) from getting to it and paint the rest of the structural components to match.

[JimD]

I wouldn't argue pine is free of splinters but it hasn't been a problem on my handrails. But they would not get nearly as much weather as other parts either. I used a router to chamfer mine at 45 degrees. So even though they are on edge the horizontal surface is further reduced by the bevel. I didn't want water to have a good chance to soak into the unpainted (or stained) surface of the PT. The tops of my 4x4 posts supporting the handrails are also beveled and exposed. They show some signs of weathering after 10 years but are still very servicable.

[Pappy]

Between working my days off, some rain on the days I was off, and a few other problems I'm still not finished. I got home early today and got the tops of the posts cut to length and primed. I have to take the wife for another injection in her back in the morning and have to hang close in case she needs me the rest of the day. I plan to paint the frame work after she is settled in and lay the decking.

I also cut a plywood template for the stringers tonight. While the paint is drying I will set the forms and pour a footing for the bottom of the steps. She wants them narrow, 25" rail to rail, so she can hold onto both rails so 3 stringers will be more than sufficient. The base will be on post bases but I'm still not sure how I want to attach the tops of the stringers. One option is to add braces between the first 2 joists and cut the top of the stingers to bolt to the braces. My other, simpler, option is to use concealed stringer hangers and attach the stringers to the outside of the end joist. Any experience with these brackets?

http://www.uspconnectors.com/pdfs/2068CSH-TZ.pdf

[os1kne]

I don't have experience with that particular hanger, but I built my deck over the summer and spent a bunch of time fretting over the best way to mount the stringers to the rim joist, which hangers to use, etc. I went a slightly different route. (Just offering an option that may be helpful to you.)

If you've already cut all 3 stringers, disregard the following. For this, the outside stringers are cut differently than typical stringers (but simpler). Sturdy angle brackets are used to mount the outside stringers to the rim joist, and "stringer bracket(s)" are used to mount inside stringers.

I prefer to mount a 2x8 below the rim joist to mount the inside stringer brackets to (could also mount outside concealed stringer brackets [like what you referenced] to this 2x10 so that the top step could be placed a step lower than the deck surface (so the top step doesn't jut out proud of the rim joist, even with the deck surface, not that there's anything wrong with it.

I've attached a pic, that may help explain. (Not a great pic - taken with my phone, in the dark. Not quite done staining the deck, so excuse the unstained under stair area.)

Good luck!

[Carpenter96]

Hi Pappy I have used hangers many times and they work great.

Regards Bob