piano too heavy for a home?

[justharmony]

Wondering if anyone's ever run into this "problem" with building structures in general... esp where old building codes might not have expressed what tolerances the floors were built to withstand.  We have the additional problem of having a shifting foundation right now - we are trying to wait for it to "stabilize" after spring thaw.  We've been told that putting 800 pounds of piano on the floor would not help matters.

I don't know what to think other than that I am going crazy with a little digital and having my dream piano in storage.  Any thoughts or experiences with anything similar out there?

It was suggested that we can either built greater support by going beneath the floor and adding some more structural support (which would involve ripping up a ceiling, at the very least) or that we could simply put a piece of plywood under the piano (under a rug) and on top of the floor with the theory that this would better distribute the weight of the instrument over a greater area.

Thoughts?  Suggestions?  Thank you!

[quantum]

If your floor cannot hold 800 lbs in a small area, there are other more pressing matters I would be worried about then getting a piano. 

Have you ever had a group of 6-8 adults huddled together for a group photo?  squished together on a couch to watch TV?  sitting around a dinning table?  This group of people would weigh around 800 lbs, and if your floor cannot hold that I would seriously question the safety of humans living in such structure. 

[hfmadopter]

Some old flooring was soft pine ( I've even seen fiber backed tiles). It's not a matter, in that case, of the structure not holding the piano but the soft pine getting gouged up. Some very old structures dating back to the 16 or 1700's could have rough lumber joists that may not be up to todays code. When you walk in those old houses ( we have some around this area) the floor gives some under foot. Most of those houses are museums these days though. They tour those houses in limited groups at a time, groups of five or six people are common. We do have a few around town that are private residences though. I'm thinking if your house has 2x6 inch ( which is not very heavy for flooring under framing) or greater construction under the flooring it should hold a piano. I could see supporting that though. It's not just a matter of how heavy but how it's supported, how wide a span they ran..

So, I assume what is being suggested it to cut into the ceiling below, cross tie some joists and put a column in the area below the pianos position? That really isn't all that big a task.  If it's basement below, a cross tie of a couple of 2x8s nailed together and a screw jacked to the joists and toe nailed in place would probably suffice nicely. That combo would bear way more than the weight of the piano, so it will help the entire floor out really. A home owner could do that job or a competent carpenter could do it in maybe an hour minus the finish work to box it in. I'm sure the foundation is a far larger task !

[iansinclair]

I live in one of those houses; it is both our home -- and a museum.

There are really three different problems.  The first is, can the floor hold the piano without collapsing?  The answer is almost certainly yes.  Consider that a grand piano weighs perhaps 800 pounds.  It is also about 5 fee wide, and, depending on the piano about 6 to 8 feet long.  That means that its weight is spread over about 20 square feet -- give or take -- for about 40 pounds per square foot.  It would be very very rare for the floor structure to be so weak that it couldn't take that (you, standing on one foot, are at least double that!).  An upright puts more load on the floor, though -- but is usually placed against a wall.  So shear strength shouldn't be an issue.

The second is the point loading of the legs of the piano.  Each leg or a grand is 200 pounds, more or less.  If the floor is at least 1 inch boards (most floors, even in old houses, are two layers, each 3/4 inch to an inch), and the joists are not more than 16 to 20 inches apart, it should be OK (assuming the boards aren't rotted!).  However, if the wood or other flooring material is soft, you might be well advised to put big caster holders (my grand is on 4 inch diameter glass holders) to spread the load so as not make a dent in the flooring.  (Ladies' high heels are a worse threat, though).

What may be a problem is the third -- deflection -- springiness.  More noticeable with the upright -- it will bow towards you as you walk towards it, which is nice of it but a bit disconcerting.  This may or may not be a problem for you; the only cure for it is to substantially increase the stiffness of the floor.  hfmadopter's suggestions can help.

[lhorwinkle]

Will your piano purchase result in a news story? "House collapses, 2 killed, 5 injured."

Skip the piano. Fix the house, or move out. Then get a piano.

[erick86]

Putting a sheet of plywood under the piano would be efficient if the concern would be that the flooring itself would not be able to support the piano.  However if it's the actual floor system itself, then putting plywood underneath probably wouldn't alleviate the problem.  You would likely need to install an additional supporting beam underneath that floor, supported with teleposts. 

Do you have any structural engineer friends?  I'm a carpenter by trade and deal with similar scenarios in century-old houses fairly often.   But it's best to get it checked out by an engineer before making a decision.  That way you can get a reliable plan in place that will bring that floor up to strength so you don't have to worry about falling through the floor when you unleash some Rachmaninoff.   

Best of luck,

Eric