Rotted sill plate replacement — no tie-downs
Hi,
1880, balloon framed foursquare. An old porch which sometime in the early 20th century was turned into an addition and a full foundation added (block with hollow core..thicker than modern block) with a porch/deck above. Turns out a small leak in the copper deck has allowed water to come in for quite some time, disintegrating the sill plate and rim joist (actually there is no sill plate just a double 2×8 rim joist).
I have to replace it but in doing so will I need to add some sort of tie down for the new sill plate? I plan on putting a treated 2×6 down for a sill then rim joist, then 2×6’s up to the double top plate sistered to the original 2×4’s ( I will cut about a foot off the bottom of the current studs to get the rot out).
If I do need tie downs how do I go about doing this? Pouring concrete into the voids and adding j-bolts?
thanks
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Replies
Geoffrey,
In earthquake-prone areas, especially in California, seismic retrofits are routine. Seismic contractors are very familiar with this work. Specialty hardware is available to make strong connections between older wood-framed buildings and concrete or CMU foundations.
Elsewhere in the country, especially in areas of the country where earthquakes are rare or unknown, there is very little interest in this type of retrofit work.
Suffice it to say that until the 20th century, all buildings stayed on their foundations because of gravity. Older wood-framed buildings were never tied to their foundations. The fact that many 200-year-old buildings are still sitting happily on their foundation is proof that, absent an earthquake or a tornado, gravity still works.
Here's my advice: visit your local building department to familiarize yourself with local code requirements. Unless you live in a seismically active area, or an area where tornadoes are common, you can probably just continue to assume that the laws of gravity will apply to your house.