Expert: Daniel Humphrey - 12/29/2007

Question
QUESTION: Daniel:
I hope you can assist me.  I have an 1890's wood framed home that has two floors and a small basement in Marion, OH.  On the first floor, I have a corner room in the front of the original portion of the house that is 10' x 9.5'.  Two of the walls are exterior walls and two are very thin (feels practically like particle board) walls.  I just purchased a Marcy MD-1559 home gym that is 309 total lbs (including the 150 lbs stacked weight) and measures 64" long x 38" wide x 81" high assembled.  The floor of this room has a slight slope.  In the basement when looking up at the rooms flooring, I see what appear to be 2" x 16'(approx.) beams (joists?) that run under the room (the aforementioned slope runs with those beams). They are spaced about 16.5" apart.  There are four of them along with what appear to be three load bearing beams/walls (the two exterior and one of the others.  From what I provided, can you give me any insight as to whether that room should be able to sustain the weight of the work out equipment along with my husband's 180 lbs on top of that safely?  If you need additional information, please let me know.

Thank you in advance for any assistance you can offer.

Sandra

ANSWER: Sandra,

A  2" x 16" joist can bear a lot of weight if it is supported well at the ends. Four of these at about 16" on center are very strong. A new floor built with these substantial joists and solid subfloor could take more than 100 pounds per square foot; for the entire room, that would be 9,500 pounds! But you're not putting your old house to that test. You're talking about just less than 500 pounds in that room, which isn't much for any room having sound materials.

My concerns:
(1) the joists are sound;
(2) the joists are solidly supported at their ends;
(3) the subflooring is substantial; and
(4) the finish flooring can take the pressure.

Check all these things to satisfy yourself that the wood and its foundation are still good.

From pictures of the Marcy MD-1559, it looks as if the weight is distributed along the entire length of the frame and also the outriggers. If this is so, then that is a good weight distribution. Now that you know where the joists are running, position the gym so that three of the joists are carrying the weight.
Arrange the weighted section so that it is nearest the outer wall, to minimize the bounce.

Daniel

---------- FOLLOW-UP ----------

QUESTION: Daniel, thank you so much for your expedient and thorough response.  I have a follow up question.  How would I confirm the joists are sound and that they are solidly supported at their ends?  There is a jack holding up a beam under the kitchen but nothing like that under this room in question.  

I would say the subflooring is likely not substantial depending on how you define that.  There is an old 70s looking carpet (not shag) in the room that is pretty much laid over what appears to be a wood slat floor (though there is a thin layer of some sort of foil (silver colored) paper thin sheet between the carpet and the wood floor.  I believe the wood floor I see when I pull up a corner of the carpet is the same wood floor I see when I'm looking up in the basement.  This floors sits drectly on the joists (obviously running perpendicular to them).

Finally, I'm not sure what the finish flooring is other than the old carpet.

As an aside, I do have a few other items in this room (two filing cabinets and some full luggage).  But I certainly don't exceed the 9500 lb weight limit!

If you can offer any additional clarifications or insights I would be most appreciative.  

Thank you and may your New Year be prosperous and blessed!

Sandra

Answer
Sandra,

To check out the joist supports, you're looking at the ends of the joists to see if they are sitting on something substantial and not rotten. And also, you're seeing how long the span is. Since you're in the corner, the span isn't as critical, but I'd say it should be limited to about 12 feet to prevent bouncing.

The jack under the kitchen was probably put there to keep the bounce down, or level out a sag that comes with age in these old houses. Something like that placed beneath this room would be good to shorten the joist span and take out any bounce; but it would be overkill if your floor is good. I'd wait and see how much bounce there is when he's working out, and then talk about putting in a jack.

These old subfloors were sometimes pretty thick and substantial. They usually ran at a 45 degree angle to the joists, but running perpendicular was common. The foil you see is probably a vapor barrier and reflecting layer for the radiant portion of the room heat. Carpet adds no strength, but it does pad out point loads and absorb vibration.

If that subfloor planking is all you have, a lot of the weight could be on just one plank, depending on how you position the apparatus. I would think of putting it at a 45 degree angle to the room, with the weighted section as near the outside corner as possible.

A workout room could use a solid wood flooring to distribute weight, and then a dense rubber mat under the apparatus to catch sweat. These mats are quite common and often come with the workout equipment. The solid wood flooring I'm thinking of would be varnished or painted plywood, at minimum--or perhaps a nice maple or oak strip floor over the top of plywood.

Dan