Bouncy floor

[lukem]

Need better pics of wall and how current joists are joined to answer that one. Get that insulation out of the way so we can see exactly what is going on there.

 

[seige101]

What is holding up the floor joists in the areas colored in red?

 

[chrisasst]

What is holding up the floor joists in the areas colored in red?

the 2 on the left, there is nothing. The studs or whatever was there were all rotted. The one on the right is nailed into the stud...

 

[seige101]

That would definitely contribute to a bouncy floor! Nothing to hold the joist in place! Looks like the need for a proper header over that window also.

 

[chrisasst]

That would definitely contribute to a bouncy floor! Nothing to hold the joist in place! Looks like the need for a proper header over that window also.

Funny thing is, it is not bouncy in that corner. Only in the middle.
Yeah that whole corner / window needs to be replaced. I just have to figure out how to put a studs there because the floor in that corner is also gone due to it rotted. That whole corner is more of a night mare than the bounce is, but...

 

[Bret Chase]

To the OP... you've got a "Balloon framed" house... the span looks to be about 18'? the only way you're going to take the bounce out is to put in a mid span beam... and actually frame under the unsupported beams.

 

[Ehouse]

I own a house built in 1817 and one built in 1890+-. Both were built with neither balloon or platform frame, but with what I'll call a hybrid post and beam where the top plate (rim joist) on a given wall is a 6"x 10" or such. This eliminated the need for collar ties or strong joist tie ins because the top plate acted as a beam both vertically and horizontally. The floor joists are more like small beams on wide centers (2' or more) and are notched into the rim joist beam on top (top chord bearing) and perhaps toe nailed into its face with no ledger. From your pics. it looks to me like that's what you have, so you can use joist hangers face nailed (use hanger nails, which are thicker) with new joists of the same depth ( 2' centers are not good for ceiling sheet rock). Also, inspect the ends of the joists where they join the rim beam, they will often be split lengthwise. if so, jack up each joist in the center and the split should close up. you can then snug it up with a hanger or plumber's strap. Adding a 6" lag about 4" back from the join will help.

 

[Ehouse]

To the OP... you've got a "Balloon framed" house... the span looks to be about 18'? the only way you're going to take the bounce out is to put in a mid span beam... and actually frame under the unsupported beams.

Could be balloon frame, pic. #3 shows studs under both joist and sister so hard to tell.

 

[chrisasst]

To the OP... you've got a "Balloon framed" house... the span looks to be about 18'? the only way you're going to take the bounce out is to put in a mid span beam... and actually frame under the unsupported beams.

So something like this.. I could put a leg in the middle. Not Ideal but....
Also I think that window on the right is dead center of the room.,

 

[Bret Chase]

I own a house built in 1817 and one built in 1890+-. Both were built with neither balloon or platform frame, but with what I'll call a hybrid post and beam where the top plate (rim joist) on a given wall is a 6"x 10" or such. This eliminated the need for collar ties or strong joist tie ins because the top plate acted as a beam both vertically and horizontally. The floor joists are more like small beams on wide centers (2' or more) and are notched into the rim joist beam on top (top chord bearing) and perhaps toe nailed into its face with no ledger. From your pics. it looks to me like that's what you have, so you can use joist hangers face nailed (use hanger nails, which are thicker) with new joists of the same depth ( 2' centers are not good for ceiling sheet rock). Also, inspect the ends of the joists where they join the rim beam, they will often be split lengthwise. if so, jack up each joist in the center and the split should close up. you can then snug it up with a hanger or plumber's strap. Adding a 6" lag about 4" back from the join will help.

It sounds like your houses are what we call "3/4 framed" in my area... basically post & beam in the walls with a conventional roof.... it's also how my house is framed... there are exactly 12 posts that hold up my entire roof... the studs are mortised into both header and sill... with no nails.

2' centers is fine for 5/8 sheetrock... but you *really* should strap the ceiling out if you're going to sheetrock it..

 

[Bret Chase]

Could be balloon frame, pic. #3 shows studs under both joist and sister so hard to tell.

perhaps you could call it.. "ballon framed, improved"? I have learned over my career... when you start gutting old houses... you NEVER know what you're going to find...

 

[Bret Chase]

View attachment 93642

So something like this.. I could put a leg in the middle. Not Ideal but....
Also I think that window on the right is dead center of the room.,

if you used a relatively small LVL or PSL engineered beam... my gut says a 5x7.. it would massively improve the upper floor... and depending on if 1/360 deflection is important... you most likely won't need the center post.

 

[Ehouse]

I think it's either beam or extra joists. If its balloon frame, beam would be easier, but you'll need a header over the window, strapping or other modification for the ceiling, and live with the visual reality of a single beam in the middle of the room. If there's a substantial rim joist/beam at the joist ends, hanging new joists will address all of the above concerns. Check the ends of the existing joists for splits which could be causing the bounce. The ceiling was built to hold up lath and plaster, so something has deteriorated structurally. You could do the beam in either case.

 

[TresK3]

I'm concerned about your comment that the floor in that corner is rotted. Do you mean the subfloor (or whatever is over the floor joists), or are the joists and other structural members bad, too? If so, you may want to address this first, before you start building/reinforcing on top of that area.

Beyond that, I'm liking the idea of extra joists in-between the existing ones; maybe even go up a couple inches in size. Make sure everything is well supported on the ends. Also, if you add a plywood floor on top of the T&G that's up there already, and really screw it down into the joists AND between the joists (into the T&G), that will help to tie everything together.

 

[backpack09]

It sure looks like your flooring is not touching your original joists in a lot of places.

Blocking between joists, installing 2x8s to sister over gaps in new joists, add 2 rows of 3" long screws every 10-12 inches to connect the existing joists together, and install an additional 3/4-1" subfloor with the weak axis perpendicular to the joists is what I would do. Beams are ugly.

 

[semipro]

OP, I guess another thing to consider:
adding or sistering to joists, adding subfloor, installing a beam without a central post, all are options that will add additional loads to what may be already overstressed or inadequate wall and foundation structures.

 

[chrisasst]

I'm concerned about your comment that the floor in that corner is rotted. Do you mean the subfloor (or whatever is over the floor joists), or are the joists and other structural members bad, too? If so, you may want to address this first, before you start building/reinforcing on top of that area.

Beyond that, I'm liking the idea of extra joists in-between the existing ones; maybe even go up a couple inches in size. Make sure everything is well supported on the ends. Also, if you add a plywood floor on top of the T&G that's up there already, and really screw it down into the joists AND between the joists (into the T&G), that will help to tie everything together.

Well the tree trucks that the floor is on ( or whatever they are) look ok. Also in that corner and that side of the wall, underneath those is the stone foundation that some of it sits on. I will try and get a picture next time I can in the day. So if I can figure out how to put wall studs there in that corner, rough a new window out, I think it will be ok there.

This room is just a mess.

 

[Eatonpcat]

Good Luck, I would listen to Iron Pony...His advice is always good when it comes to structure!

 

[jharkin]

To the OP-
It sounds like you have extensive structural issues to address, especially in that exterior wall. A book I highly recommend is Renovating Old Houses by George Nash. It documents a lot of structural techniques that might apply. Caveat in this situation if it were me I would take the book just as a starting point to get ideas and probably want to bring in a pro.



Some more about framing methods. This is what a true balloon frame looks like for anyone interested:

First known balloon frame building was around edit 1832 1840ish. Before that everything is post and beam, though there are lots of variations in how post and beam is done. Some had no studs at all and plastered the sheathing directly, others had studs at odd intervals to support the interior wall finish. And then there are variations like plank framing that had had continuous 1-2" vertical boards mortised into the sills and plates (eliminating the bracing). Plank houses are especially tough to update as the plaster is typically applied right to the inside of the planks leaving no cavities to run wires or insulate.

After the civil war balloon framing started to spread, first popular out west, but it didn't reach New England until the late 1800s You can find post and beam houses in NE up to the 1860s and later, and even after that they would build a hybrid called a "New England braced frame" , that was a balloon frame with post and beam type Corner posts added and some knee bracing. After 1900 I think its mostly pure balloon framing and then platform framing sometime before WW2.

Ehouse, of course am no expert, but your 1817 house sounds like standard post and beam construction (both my mud sills and top plates are 6x7 beams) and the 1890 house is probably the New England hybrid frame type I described above.

Anyone who has real interest in this stuff, there is a great book called A Building History of Norther New England that shows the evolution and has drawings of each type. Its a great resource written by the first curator of the Strawberry Banke Museum..

 

[jharkin]

Ehouse, does this look familiar to your 1890 house?

 

[Ehouse]

You're probably right on the older one, post and beam with stud infill. Late 1890's house a little different in having the full size beam for the very top plate but otherwise, that's pretty close. A surprising feature to me of both houses is the lack of collar ties, king post, queen post or ridge beam, with fairly slim rafters from plate to peak and notched together. With rough sawn skip sheathing, I wonder how they've withstood shear forces for all these years. If the carriage barn is any indication, the house is probably framed mostly with Chestnut and Yellow Birch (bark still on).

Many of the older Victorian style homes in this area are apparently kit houses from Sears and Roebuck right down to the interior trim mouldings. I wonder what framing they used?

 

[G-rott]

Engineered lumber is great for beams if you have the head room, two beams at 1/3 span would allow a shallower beam and possibly easier framing. If headroom is a factor you could cut you beam by supporting both sides and cutting out space for the new beam and hangers.

Don't rule out steel if headroom is a major factor.