DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Carpentry (
-   -   Floor joist replacement and reconfiguration (

WillK 08-31-2011 01:39 PM

Floor joist replacement and reconfiguration
At this point in the realm of projects on our house, the top issue seems to now be the unevenness of the floor, so I'm going to start on the floor joist replacement. I've considered my options between sistering and replacement, and I am at this point of the strong opinion that replacing the joists and subfloor and rim joist is the better route because:
1) most of the rim joist is rotted away anyway
2) most of the floor josits have been sistered at least once because the end of many joists rotted with the rim joist
3) the 2x6 lumber is undersized for its span
4) I will be more sure that the floor will end up flat and level by building new instead of repairing old
5) the floor plan will be changed through future projects anyway
6) existing structure does not properly support penetrations for plumbing or crawlspace access nor provide extra support where needed for higher load items like the bathtub or stairway.
7) the only existing beam is undersized and has unsupported joints.

Anyway, the case can be made for starting over completely on the house, but there are practical limitations which take that out of consideration.

Getting to my question, here's the background which directly relates to my question:

The house was originally constructed in 1917 as a simple 22x22 gable end 1.5 story house with the gable ends facing east and west and floor joists oriented north-south. As a later time, an additional 10' was added onto the east end of the house, this addition used floor joists oriented east-west. In other words, the last 10' of house has floor joists perpindicular to the floor joists of the rest of the house.

It seems to me that the prudent course of action as I replace floor joists would be to replace the east-west floor joists with new floor joists oriented north-south as it is with the rest of the house. This will also simplify the beams I am constructing because they will simply run the span of the house instead of building something like an H-shape.

Is this the right way to proceed or are there any reasons to stick with the original configuration?

My building inspector is fine with deviations I've planned from my engineer's specifications so long as they exceed his specifications, such as I've increased the number of footings (the original spacing would have interfered with plumbing), I'm using 4 beams instead of 3 (due to furnace placement in the crawlspace) and upsized joists (originally specified as using the existing 2x6 joists)

BigJim 08-31-2011 04:35 PM

I would run the floor joists where they tie the weight bearing walls together. I have seen the rim joists roll under the weight of the roof and ceilings without the floor joists securing them. The walls I have seen even had blocking but were built back before cement coated nails came out so the nails were commons which don't hold well especially in the end grain.

If you plan to replace the joists, may I suggest replacing them a few at a time, if you remove too many at a time, the walls could spread at the base as the outside band may roll without the joists holding the band in place.

WillK 09-01-2011 08:01 AM

Good points, I'm rethinking my approach a little bit.

My plan originally was that I would replace joists along one side of the house. The joists being oriented north-south, I would start at the first joist on the west then move towards the east. Along the way I be altering the floor plan so that the load bearing walls for the new rooms would go up along the way supporting the second floor as old walls came out.

If I take this into consideration, it sounds like the best approach would be to replace joists along their full length so that new joists tie one side of the house to the other before moving to the next joist.

For what it's worth, if by band you mean rim joist- that is rotted away and will be part of the project to replace it. The sill plate also is garbage and will be replaced.

All times are GMT -5. The time now is 10:12 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1