Non treated Hemlock/hemfir will rot so quickley you will have to stand back while it goes. The treaters like it in some areas because yellow pine is not local but they have to line it to make the chem take. Treated hemlock would look a little funkey as decking but would probley last as long as .25 treated yp the box stores sell. J.

Oh, boy -- that doesn't sound too good! Considering that my deck requires a thick (approx. 2-3/4 in.) plank, what would you recommend for wood species? Thanks!

Here's a photo of the underside of my deck. Hopefully the photo is clear enough to see that the 8-ft-on-center joists continue inside, and are a design element of our bi-level house. While the lower level design isn't anything to rave about, I still think that I would prefer not to alter the look of those interior/exterior joists.

As such, any suggestions for wood species for floor decking? You can see how thick the existing planks are if you look right below the side railing. Thanks again.

That makes a Pinto out of a Paint, a horse of a different color.Looks like the decking is done with 6 x 8 timbers defentley biger than 2 3/4'' material.

If the decking is needing replacement be sure and check the top of those beams they almost surley will have some soft spots in the top. Also inspect the entry area where the beams go into the house.
That span requires the 5 1/2'' thick or larger like it has now but even with that its going to bounse a little. Either add more beams/joice system or go with all heart cvg Redwood,old growth doug fir timbers. Both of them will probley have to be custom milled and will be a little spendy....ok a lot spendy.

John wondering>> how long were the fasteners on that decking??

Thanks, John. But I'm confused (a frequent state of mind when it comes to home repair). The planks we have now are 2 3/4-in. thick (I measured it). So far as I know, the deck is as old as the house -- so about 30 years now. We've lived here half of those years, and when we bought, there were a couple of deck planks that were starting to rot. So it took a while, but definitely time to replace now.

With the possible acid flashback from another life, I am looking at the extended ends of what look like the decking and they are defentley not 2 3/4'' thick. The ends compare to the holding planks for the beams in size from the picture, they are not 2 3/4''.

Possible cause of contradiction in order.......1 the decking was cut down so only the ends are 5 1/2'' or so thick,2 The picture has been modified,3 the picture is old and the decking is now 2 3/4'' thick,3 or I am in an acid flashback and will never see that picture corectley.

With the given that #3 is out of the question.......

The decking in the picture is not 2 3/4'' thick if the picture is showning me what you want it to.

Intersting exchange. John Mon

mjlb - judging by your choice of landscaping features of rocks and snow, a very common look in the NorthEast, I'd have to guess that you are from ... the NorthEast.

Not meaning to contradict anything that Master Deck Build Mr. Hyatt, but just want to clarify on our local cash crop of hemlock trees. While the good ole boys from the NE bestow much favorable comments on our local hemlock lumber, Mr. Hyatt, being a good ole boy from Okie, may not be familiar with the genuine stuff, the stuff that clads almost every old red barn, around here. Said genuine hemlock is fit for most exteriors, but above grade only.

Problem with your application, though, hemlock is soft, soft as local pine. Do you want heavy traffic on that? Or is this more of a "lookin at" deck?

On the other hand, you could "up the ante", and ask your builder for a quote on some local cut black locust. That stuff will be there after you are dead and buried. Like maybe a 100 years after you are dead and buried.

Ask for samples/scraps of whatever you are considering using for the deck.

As far as your spans, I have no idea. John Hyatt knows his stuff.

If you are going down the "straight and narrrow" with this, the guy at what John Hyatt calls the "permit store" is a must visit - the building inspector. If you are getting a permit, you might as well ask him right now what he thinks. He will tell you eventually anyway.

Some of the permit rules are stupid ("handicap access" on private property, equipment efficiency, etc). The strength of your deck floor is purely a safety call. The building inspector is there to help you. He will know about loads.

I tell you Tom Mon, Over Eugune Or way we cut a lot of hemlock, I have used it and I know that old growth suff would rot in a NY Min. We usta call it Bamm a short cut to its bio name.

You be Damm Straight about that my man I am a good ol Boy Okie. Also this ol boy knows what hemlock does exposed flat to the sun and fastened to the joists. Siding is one thing decking is another. J.

Well maybe the hemlock works only vertical, not horizontal. Maybe you are right about that. Could be. My local sawmill guys says nail on the side of your barn, then forget about it. No need even to stain it, watch it turn black.

One peculiar thing about this Northeast Hemlock is how slow it grows, very tight grain. It's mostly about 1/16". When I bought my hemlock boards (this past summer), the guy said they just cut one that was over 350 years old. Did you see them like that in Eugene?

My deck is ipe planking, garapa rails/skirt and hemlock lattice (I did stain the lattice).

{{gwi:475142}}

Those were old growth trees 4/ 6' at the butt no telling how old they were. Its just soft wood without the built in protection doug fir has.Hemlock is the lumber of choice up there for treating but like I said it has to be lined before going into the retort,makes the lumber look kinda goofe. J.

Yep - it is New England. Too much snow right now, but the deck gets plenty of use -- it's not just for show. I've heard of black walnut, but never black locust -- I'll have to look into that.

For an uncovered, but elevated, deck located in New England: how does #1 Kiln Dried Western Red Cedar with eased edges sound for durability?

Nominal dimensions would be 3-in thick, 6-in wide, and about 16-ft long. I'm hoping it's an improvement over initially proposed hemlock? I had to rule out the ipe alternative for cost reasons.

Thanks for any input!

I know this is a few month old thread now, but just wanted to add my experience with Hemlock for reference...

In upstate NY here...have a short (6') inclined ramp to my shed...used hemlock 2x6 rough cut (full dimension) boards on it, milled locally. First round lasted about 7 years before decay started setting in..."second round" of replacement boards has gone 3 years so far with no sign of decay yet. This is of course never shoveled off in winter, untreated, unstained, etc etc etc. Long and short though, definitely not suitable for decking.

I will say though, the full dimension 6x6 beams holding the ramp up is still as solid as could be though!

Also, have used hemlock for the floor structure (elevated, no ground contact) of an elevated playhouse project with great success. As long as it is off the ground and not in the rain/snow/etc, it lasts well.

Glad I missed that bullet then. Hopefully the western red cedar will hold up longer -- just gave the contractor the go-ahead.

Good luck with it! I do think the western red cedar will hold up longer than the hemlock, though it might be a bit softer and weaker.

I do use hemlock alot around the yard for misc projects, but always with the understanding it is going to rot at some point, so I don't use it in any applications where there are safety issues or concerns about longevity. I would point out too that the rot always occurs (for me) at contact points with other wood (i.e. where it doesn't have good air flow to dry out). As I said before...the 6"x6" hemlock beams holding the ramp up are as solid as can be, no sign of rot at all after 10 years...I guess the biology like the thinner stuff *grin*.

You (or someone) mentioned black locust...I found out not long ago that our local mill does mill that from time to time (I think custom order). I can tell you this, there are black locust fence posts back at my parents home in rural central NY snow belt country that have been in the ground 70 years and still standing (I know, my dad put a few of them in when he was a teen back in the 40's). I think it is the hardest domestic wood we have...

On a side note, I am really curious about your deck structure. John was indicating that he thought those deck timbers had to be bigger than 2 3/4", and I am scratching my head as well. It is so hard to appreciate the "scale" of things in the picture, but I look at those ballusters and assume they are 2"x2"? Then I compare them to the thickness of deck boards, and it seems like they are a lot closer to 6" than they are 3"! Also, 8' is a large span for wood less than 3" thick. Anyhow, would love to hear more about the dimensions of the structure...can you confirm too that we are indeed looking at the decking from the side, just under the railing? Just want to confirm the decking isn't sitting on "top" of what we think is the actual decking...

I really like the look of that deck from below though...whoever built it was really thinking of how it was going to look from that room below.

Good luck with the project!

I'm may be misusing terms, but the beam is 11 inches high and 3-1/2 inches wide. The planks on top are 2-1/2 inches high and 5-1/2 inches wide. The overall size of the deck is approximately 8-ft by 16-ft, with each plank being about 16-ft long, by 5-1/2 inches wide and 2-1/2 inches high.

The balusters (small uprights in the railing) are only an inch wide -- Could that be what is distorting the apparent scale?