I seem to remember hearing or reading somewhere that when building benchwork, lumber in direct contact with concrete is not a good idea, as the lumber will dry out and start to rot sitting on the concrete. Is there any truth to this??? Thanks
Popi
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My last layout was up 15 yrs in a basement with the wooden legs touching the floor and I had no issues.
-Greg
My basement layout is at 25 years and zero sign of any issues with the 2x4 legs.
Limited concern. Wood framing attached/glued/nailed to concrete (most often the floor) can be done with treated (wolmanized) lumber. Dry environment/low humidity is a very good idea. IMO, Mike CT.
I don't know, However I put levelers on all my benchwork legs.
If the concrete has any dampness, it could be an issue. Best bet is to do what Clem has done. Place some kind of rot proof material between the leg and the concrete. Home Depot and Lowes have all sorts of products specifically meant for this purpose.
Many years ago some DYI-guy finished the basement in the house we now own. He laid 2X2 plates (for stud wall) directly on the concrete floor and by now there is some obvious rot on some of it. Has been many years though.
I'd do what Clem K did: drill a hole in the bottom of each leg and install a screw-thread leveler. Kill two birds with one stone (leveling and rot prevention) :~)
Lew
geysergazer posted:Many years ago some DYI-guy finished the basement in the house we now own. He laid 2X2 plates (for stud wall) directly on the concrete floor and by now there is some obvious rot on some of it. Has been many years though.
I'd do what Clem K did: drill a hole in the bottom of each leg and install a screw-thread leveler. Kill two birds with one stone (leveling and rot prevention) :~)
Lew
And if you're talking about putting studs vertically up against a concrete wall, get a small roll of adhesive ice and water shield (Grace) and run it along the side of the stud facing the wall.
Finished basements have walls...some are built on concrete floors with wood-stud walls and they do not rot. Like the others have said, if it is not in a damp area, I wouldn't worry about it at all.
Popi posted:I seem to remember hearing or reading somewhere that when building benchwork, lumber in direct contact with concrete is not a good idea, as the lumber will dry out and start to rot sitting on the concrete. Is there any truth to this??? Thanks
Popi
It's not that it dries out. Moisture passes through concrete. So lumber in contact with concrete can wick up moisture and rot. It's a cause of concern with foundation sill plates and base plates on walls if you're framing out a basement. I wouldn't worry about it when it comes to a layout. If you were concerned about it, the easiest thing to do would be to paint the contact points with some Kilz or put a piece of membrane (Lowe's/HD) in there. But since the layout isn't entombed (drywall, etc.) the amount of moisture that will get trapped between the lumber and the concrete is miniscule. As long as the relative humidity in the room is low, it won't be a concern.
In my last house my layout with 2x3 legs was up 24 years and I am using the same lumber in the construction of the benchwork in our new house. A dry basement is the key and more important that dry for the lumber it should be dry to protect the trains.
Years ago there was an article about using carriage bolts and T-nuts on the legs as a good way to level a layout on uneven floors. I found (the hard way when the washer hose burst) the added advantage was it kept the wood studs off the concrete and away from minor flooding. A little effort but not difficult.
We used a star nut, and drilled hole, set in the bottom/ floor end of Fort Pitt Highrailer modular legs. An eye-bolt makes a good adjustable leg. IMO. The bolts do require some maintenance/oil from time to time. Finger adjustment or a screw driver through the eye-bolt for additional torque, if required. 5/16" or 3/8" eye-bolts, with star fitting will work. accurate, long/deep, straight hole needs to be drilled in the leg about 4" works best.
Mike CT posted:Limited concern. Wood framing attached/glued/nailed to concrete (most often the floor) can be done with treated (wolmanized) lumber. Dry environment/low humidity is a very good idea. IMO, Mike CT.
gotta disagree with you on this one Mike, been in construction for many years and using treated lumber in doors is questionable at best
Popi posted:Mike CT posted:Limited concern. Wood framing attached/glued/nailed to concrete (most often the floor) can be done with treated (wolmanized) lumber. Dry environment/low humidity is a very good idea. IMO, Mike CT.
gotta disagree with you on this one Mike, been in construction for many years and using treated lumber in doors is questionable at best
Usually treated lumber is wet and the dimension changes as it dries, I would agree to disagree. 
Better choice Redwood if available, or cedar, though cedar tends to have limited structural value. IMO, Mike CT. Older homes, on occasion, you would find Douglas Fir, which appeared to have good integrity after many years.
Mike CT posted:Popi posted:Mike CT posted:Limited concern. Wood framing attached/glued/nailed to concrete (most often the floor) can be done with treated (wolmanized) lumber. Dry environment/low humidity is a very good idea. IMO, Mike CT.
gotta disagree with you on this one Mike, been in construction for many years and using treated lumber in doors is questionable at best
Usually treated lumber is wet and the dimension changes as it dries, I would agree to disagree.
Better choice Redwood if available, or cedar, though cedar tends to have limited structural value. IMO, Mike CT. Older homes, on occasion, you would find Douglas Fir, which appeared to have good integrity after many years.
I like that idea of cedar lumber. it would make the train room very aromatic!! 
Popi posted:Mike CT posted:Popi posted:Mike CT posted:Limited concern. Wood framing attached/glued/nailed to concrete (most often the floor) can be done with treated (wolmanized) lumber. Dry environment/low humidity is a very good idea. IMO, Mike CT.
gotta disagree with you on this one Mike, been in construction for many years and using treated lumber in doors is questionable at best
Usually treated lumber is wet and the dimension changes as it dries, I would agree to disagree.
Better choice Redwood if available, or cedar, though cedar tends to have limited structural value. IMO, Mike CT. Older homes, on occasion, you would find Douglas Fir, which appeared to have good integrity after many years.
I like that idea of cedar lumber. it would make the train room very aromatic!!
Yes the cedar would be nice as it would bring back a lot of memories on using AF smoke fluid
Surprisingly I used an MDO plywood board on the layout. MDO has a composite layer with some cedar.
Popi posted:Mike CT posted:Popi posted:Mike CT posted:Limited concern. Wood framing attached/glued/nailed to concrete (most often the floor) can be done with treated (wolmanized) lumber. Dry environment/low humidity is a very good idea. IMO, Mike CT.
gotta disagree with you on this one Mike, been in construction for many years and using treated lumber in doors is questionable at best
Usually treated lumber is wet and the dimension changes as it dries, I would agree to disagree.
Better choice Redwood if available, or cedar, though cedar tends to have limited structural value. IMO, Mike CT. Older homes, on occasion, you would find Douglas Fir, which appeared to have good integrity after many years.
I like that idea of cedar lumber. it would make the train room very aromatic!!
the other reason I don't like the idea of treated lumber is, years ago before the local municipalities went to transfer sites and we still had local dumps, a friend of ours was in charge of the local dump. he was scavenging scrap wood (including treated), to burn in his wood stove at night. he ended up dying from inhaling the wood smoke from years of burning treated lumber.
mjrodg3n88 posted:Finished basements have walls...some are built on concrete floors with wood-stud walls and they do not rot. Like the others have said, if it is not in a damp area, I wouldn't worry about it at all.
Many Codes require that pressure treated lumber be used for the bottom plate when framing a basement. The concern, as others have stated, is the humidity coming up through the concrete floor. Untreated wood will absorb the moisture. However, if the basement is not damp, regular lumber for the layout benchwork will be fine.
Your question and this conversation made me go downstairs and take a look. The layout went up in 1995. I see no warping at all, nor any sign of rot. The wood seems the same as it was when first purchased and delivered .
I'm glad for the cautionary posting, however. It certainly was informative reading the replies here, several of which come from backgrounds and experience far more pertinent to your question than mine.
Ancora Imparo
FrankM
The rotting would start at the bottom of the legs where it contacts the concrete.
I used to work as a engineer for Portland Cement Association. The only issue with a concrete basement floor and a layout is levelness. Typically the basement floor is poured and formed in the dark because it is done after the first floor is constructed. So the workers are in a unlighted basement trying to slope the concrete floor to a drain.
The eye-bolt idea is a real good one because it lets you continually level the layout if necessary.
If you are worried about the fir/spruce touching a concrete floor and puling moisture up.
Just put the leg where it meets on the floor into one of this disposable food containers or small bucket as a barrier.
You must get some flood in the basement, if you do not you may want to try a dehumidifier?
My layout's been up for 35 years with the legs in direct contact with the concrete floor. Even after 2 basement floods with about 4" of water, no issues.
Rusty
NJCJOE posted:The rotting would start at the bottom of the legs where it contacts the concrete.
I looked. It is all okay. Thanks for the additional info.
I thought you weren't supposed to use treated lumber indoors as it released toxic gases.
E-UNIT-79 posted:I thought you weren't supposed to use treated lumber indoors as it released toxic gases.
I would not only avoid treated lumber in doors but would not use it to frame out a vegetable garden or build a deck.
Product used, where moisture is a possibility. Some codes require it to be used for window and door installation.
Most treated lumber has a small warning tag attached to an end.
I used 1/4 x 3 Powers Wedge-Bolts Concrete Anchors in one of my layouts for leg leveling bolts. Although made for concrete, they work perfectly fine in wood applications too, much like a lag bolt.
The main shank is 1/4" dia., the outside of the threads is actually 5/16" dia. I probably used a 9/32" dia drill bit for drilling into the leg bottoms (been several years ago now). A 1/4" dia. hole wood be most likely be a little too tight and risk splitting the wood.
Their BEST feature that I found attractive was the extremely coarse pitch of the threads. One full turn of the bolt advances it 7/16". A lot less messing around when turning bolts to level up some framework.
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