Sprung Deck?

[kenour]

Hi All,

I was thinking lately about the deck I'm about to build, and had the idea of putting a little spring in it.

Just for a bit of comfort under foot. Just wondering if anyone has ever thought about, or done anything like this?

My idea was to put suspension bushes in between the joists and bearers, hopefully to get uniform spring under foot.

Now I'm not talking about a spongy deck where the joists/bearers are spaced too far apart. It's going to be solid, I'm just after a uniform spring.

After working on concrete slabs all day, would like to take the stress out of my knees when I get home to relax!

Not talking about a huge spring like a boxing/wrestling ring, just enough so it feels close to wearing a pair of crocs ;) #dadlife

Cheers.

[cava]

Timber decking is naturally forgiving to legs/back vs concrete. If you were to introduce 'extra' give, you probably would not like it.

I remember years ago various people used to put two (2) layers of underfelt under carpet, for just the same reasons. It did not work, and caused more leg/muscular issues in particular.

[kenour]

Yeah excellent point. I'm worried about it being too stiff because the subfloor will be constructed completely from LVLs.

I was only thinking a 10mm or so bush at every point a joist hits a bearer. Only want a few mm deflection.

[cava]

Perhaps visit someone with a good timber deck and spend sometime on it to gauge how it would feel. Remember timber is, by it's nature, incredibly forgiving.

[Gabriel]

Just on a side note, lvls for sub floor.... Whilst I have used them regularly in houses, I was under the impression that in external use they would delaminate. Is there an external LVL available or are my impressions incorrect and they would be fine for external use?
Just wondering, not a critisism by any means

Cheers
Gab

[Kuffy]

We just sent a pack of LVL back to the merchant yesterday because they had ripped wider boards down the guts to fill our order of 140's/120's. We store them outside in the rain, and the exposed cut will delaminate in no time. Though the coating that they put on it does do a good job of repelling water, ie. no visible water ingress can be seen when I cut through a piece which has been is dripping wet for a couple of days. I don't think the coating is waterproof, more so that the LVL's get to the end user before rotting in the timber yards.

[kenour]

Perhaps visit someone with a good timber deck and spend sometime on it to gauge how it would feel. Remember timber is, by it's nature, incredibly forgiving.

When we built the deck for this project Residential Project 4 - Renovative: Quality Builders & Renovations - Ballarat, Geelong, Melbourne (http://renovative.com.au/portfolio_page/residential-project-4/) (scroll to the bottom), it was very rigid, not super uncomfortable but hardly any deflection. The deck board were 25mm thick though. I'm considering Kebony decking at probably 22mm.


Just on a side note, lvls for sub floor.... Whilst I have used them regularly in houses, I was under the impression that in external use they would delaminate. Is there an external LVL available or are my impressions incorrect and they would be fine for external use?
Just wondering, not a critisism by any means

Cheers
Gab

When using externally you can order them H3 treated (H2S by default), seal any ends you cut with a good quality sealer, and cover the tops with a fully adhered system like vycor deck protector.

[Gabriel]

Cheers for that... Something else to research a little and add to my repertoire....

[kenour]

Cheers for that... Something else to research a little and add to my repertoire....

Just wanting to try something a little different, you know! Something to add to the options for high end builds. If nothing else, it's gives the clients a talking point at their next dinner party :)

[Gabriel]

That's the problem with 90% of out work. It either gets covered or the only time it gets noticed is if it isn't done correctly (like straightening walls etc)...

[kenour]

That's the problem with 90% of out work. It either gets covered or the only time it gets noticed is if it isn't done correctly (like straightening walls etc)...

Damn straight! Just about to finish the bosses house, huge build, but all that work... covered. I'm trying to convince them to use LSLs for large walls that have raking light on them, take out one of the issues right at the start!

[ozka]

Im assuming you are thinking of using a rubber isolation type bush such as the type used to mount generators/compressors etc. Without knowing the size of the deck, your suggestion of putting them between every joist and bearer would require far too many.

If you really want to go down this path, maybe put them between the bearer and the stumps. These rubber isolators are available in many sizes, so maybe try to find some about 50mm-75 mm diameter, and about 30mm-50mm high, with a hole in the centre (usually a threaded steel insert) Epay is the go, direct from China. Slip them over the stump steel pin, between the ant cap and bearer, held down via the stump pin being bent over the bearer at a consistent tension to all of them. Or maybe leave them floating if the bearers are nice and straight. Before the bearer goes on, Id even cover them with a square of poly flashing or something that will keep the sun and rain off them to limit deterioration.

Having personally built many decks during my carpentry career, I'd be extremely interested to see this work in progress, including many pics.
Will either be a great idea that really pays off or possibly a total waste of time. Visitors may think the deck is going to collapse with the spring.

[kenour]

Im assuming you are thinking of using a rubber isolation type bush such as the type used to mount generators/compressors etc. Without knowing the size of the deck, your suggestion of putting them between every joist and bearer would require far too many.

Yeah that's exactly what I was thinking of using, deck is 11m x 4.3m, will need 55 bushes, have already priced it, can do the lot in nolathane for about $150.

409111


If you really want to go down this path, maybe put them between the bearer and the stumps. These rubber isolators are available in many sizes, so maybe try to find some about 50mm-75 mm diameter, and about 30mm-50mm high, with a hole in the centre (usually a threaded steel insert) Epay is the go, direct from China. Slip them over the stump steel pin, between the ant cap and bearer, held down via the stump pin being bent over the bearer at a consistent tension to all of them. Or maybe leave them floating if the bearers are nice and straight. Before the bearer goes on, Id even cover them with a square of poly flashing or something that will keep the sun and rain off them to limit deterioration.

Would only need 15 if I did it this way, but I don't think the feel/spring would be uniform enough? Doing it this way each 2.75m x 2.15m section would have a bush at each corner, as opposed to each 2.75m x 430mm section. I think if I went this way, any spring the bushes may impart may be lost simply due to the static load of the deck itself? Wouldn't know without looking up the properties of the bush I intended to use. Also, I was thinking that using multiple 10mm or so bushes rather than fewer 30mm ones, give a little insurance against the bushes degrading and the deck bottoming out. If things go wrong, would rather the deck drop 10mm than 30-50mm! :P

As for protection, I'll probably just run a bit more vycor over them. Deck is completely enclosed between the house and a retaining wall.


Having personally built many decks during my carpentry career, I'd be extremely interested to see this work in progress, including many pics.
Will either be a great idea that really pays off or possibly a total waste of time. Visitors may think the deck is going to collapse with the spring.

Me too, that's why I want to try it! Someone has to jump first, it's usually bloody me.

[kenour]

Cheers for that... Something else to research a little and add to my repertoire....

Just further to this, I thought it best to include this extract from the SmartLVL15 Design Guide (Edition 1, 2015). :)

409846


So you have a bit more ammo than 'SOME BLOKE ON THE FORUMS TOLD ME!'... Don't you just love the insufferable old timers so set in their ways and unwilling to learn new products/methods. :doh: I'm surprised we're all not still living in caves. "Ugh, a house, you don't need THAT, I've been digging out caves for donkeys!", and so forth... :q

[Gabriel]

Saw a chippie eyeing off my gas gun about 3 years ago....
Said to his son (apprentice) 'geeze, that goes alright'....
He had one of the '70's senco bricks and the oldest compressor ice ever seen (that includes in the antique section here)....
I just felt sorry for the son as sure he will learn a trade and be able to hand nail ob frames, but it will take him a year instead of 3 months....
Always open to new ideas... The day you stop taking notice if new innovations you may as well retire ....

[kenour]

I've got a lovely bunch of LVLs...

Guess this means I've gotta start digging some holes.

410056

Not sure I'll persevere with the spring idea at this stage though. I would still have to design the detail around the bearer/joist interface to allow the spring functionality to work, but still maintain a solid connection in a way that prevents uplift and avoids squeaks/wear... I'm sure there's something out there from another industry I could adapt, but I only have this week and the long weekends following to knock this over. Next time!

[kenour]

Just a question about the stumps on this, now boring, normal deck :P

I have 58mm bearers that are so close to the ground that I don't need stumps, just wondering what hardware people often use?

Just use the stirrups for 75mm posts and ignore the gap either side? Put packers in the gaps? Install on an angle to maximise bearing surface and screw from below?

Cheers :)