Adding foundation sill plate anchors when not required?

[bsf]

Michigan. 2 – bay garage was added to existing 1950’s home 1 – bay at a time between ~1950’s and - ~1980’s. Typical 2x4 stick framed construction for all. Open cell, 8x8x16 CMU (concrete block) foundation walls on footings for all. Garage foundation walls are only 2 – blocks tall. No apparent original anchoring to prevent uplift of foundation walls to footing or of rough sill plate to foundation. Probably some spikes driven through the sill plate into the CMU’s or mortar to inhibit lateral movement. All typical construction for timeframes and region, AFAIK.

Unless I trigger a requirement and/or AHJ demands it, would you concern yourself at all with any attempt at anchoring the garage, 2x8 sill plate to footing to prevent uplift?

I am in the planning phase of some structural improvements for the relevant garage that will essentially leave all existing structure in place except for the ceiling in the older bay. However, I will likely extend the depth of the load bearing walls inward to provide bearing for new ceiling joists. If I were to tie framing to footing in any code-prescriptive manner, it would likely most efficiently be done before plywood interior wall covering is installed on the new framing. However, my initial thoughts are it, barring AHJ requiring it, essentially being a waste of time as the attached house has no anchoring to prevent uplift, nor will it likely ever.

 

[strutaeng]

No issues, and seems like a wise move on your part. Is the CMU grouted at all?

If not, how would you anchor to the sill plate? Does the CMU have rebar dowels into the foundation?

 

[billconner]

If you can see into cells, stick in an anchor and pour some grout in, a cell every 6'. Cheap insurance. Might have to stuff something in 2 or so courses to limit grout.

 

[jack stand]

50 years +/- without issues.
Kinda sums it up for me.

 

[Zeke]

Michigan. 2 – bay garage was added to existing 1950’s home 1 – bay at a time between ~1950’s and - ~1980’s. Typical 2x4 stick framed construction for all. Open cell, 8x8x16 CMU (concrete block) foundation walls on footings for all. Garage foundation walls are only 2 – blocks tall. No apparent original anchoring to prevent uplift of foundation walls to footing or of rough sill plate to foundation. Probably some spikes driven through the sill plate into the CMU’s or mortar to inhibit lateral movement. All typical construction for timeframes and region, AFAIK.

Unless I trigger a requirement and/or AHJ demands it, would you concern yourself at all with any attempt at anchoring the garage, 2x8 sill plate to footing to prevent uplift?

I am in the planning phase of some structural improvements for the relevant garage that will essentially leave all existing structure in place except for the ceiling in the older bay. However, I will likely extend the depth of the load bearing walls inward to provide bearing for new ceiling joists. If I were to tie framing to footing in any code-prescriptive manner, it would likely most efficiently be done before plywood interior wall covering is installed on the new framing. However, my initial thoughts are it, barring AHJ requiring it, essentially being a waste of time as the attached house has no anchoring to prevent uplift, nor will it likely ever.

You can't tell if that's the case or not? I think I'd go poking around more before making any decisions or assumptions.

Anyway, sounds like your new walls could very well serve the purpose. Drawings always help and of you're permitting, you will need the details.

 

[driftpin]

50 years +/- without issues.
Kinda sums it up for me.

"If it wasn't broken, don't fix it" seems to be your opinion. I see nothing wrong with adding grout and L-anchors or some other type of structural strength pin (Hilti). I suggest doing it at a four foot spacing however. Any new addition should require it.

 

[bsf]

50 years +/- without issues.
Kinda sums it up for me.

That is my initial thought. However, being the project is not happening soon, I can mull it over, considering other’s opinions.

You can't tell if that's the case or not? I think I'd go poking around more before making any decisions or assumptions.

Anyway, sounds like your new walls could very well serve the purpose. Drawings always help and of you're permitting, you will need the details.

All I have found is 16D’s driven through the plate into blocks of wood wedged into a core in the newer garage bay. I can bore some inspection holes and use my endoscope. I forgot I have that. Maybe some time next week.

 

[walta]

Keep in mind the building code is the absolute minimum quality building allow by law. So yes, you can do better if you chouse.

If your plan is to build on top of this existing structure you may well be required to bring the old work into compliance with the current code.

Seems to me most project on this site tend to go beyond the absolute minimum required.

Walta

 

[Mick56]

Much easier to put some anchors in now, than to wish you had done it, later.

 

[Pen & Wrench]

So far so good, but then again, with crazy storms popping up here and there, maybe its time to beef it up a bit. If you ever sell it, or if your estate sells it, maybe it will be worth more or sell better if it is updated. If you have kids, its one less thing they have to think about if you leave the property to them. Just my 2 cents worth.

 

[nadogail]

If there is any doubt; I suggest you build it stout.

 

[bsf]

Ok, the overwhelming consensus is to install anchors.

I intend to inspect a bunch of core columns this week with my endoscope. Due to some cupping of portions of the 2x8 sill plate at the inside edge of the CMU’s, I can see the tops of some CMU’s. There is no grout fill to the top anywhere visible. I suspect I will find the bottom of the 2 – rows of CMU’s is simply bedded in mortar w/o any vertical footing rebar & grout fill.

 

[matt_i]

If it were on a ~4" slab then easy, you'd need an SDS bit about 18" long and then drill all the way thru to the dirt. Threaded rod down with large unistrut washers (or bigger squares) and nuts on both ends. Coat with silicone grease to try to stave off water/corrosion. Bury the small hole back which won't affect much.

However if its a solid foundation then it becomes more difficult. I'd go with a number of Z-shaped welded brackets made of box tube that sits on the 2x8, vertically down the inside of the wall, and finally bolt to a tab that concrete-anchors to the inner slab. Sort of unsightly, yes, but it will reinforce the structure.

One could try a variant of above to use an epoxied rod all the way into a solid foundation but it would require some special tools to be made, you'd need a blow-gun pipette where you could get to the bottom of the drilled hole in the concrete to repeatedly blast it out, and then you'd want to vacuum thru same, over and over. That's just the first problem. 2nd is getting the epoxy actually in the hole. I think you'd have to heat it up (thinking caulking tube) with a hotbox to get it flowing better. Precoat the threads with a gloved hand. There may be a manufacturer with an 18" mixer tip where you could inject it into the bottom of the hole, but see also warming up the material to make it flow thru the circuitous (and thus flow-restrictive) pathway of the mixer tube.