Maximum sleeve size in grade beam

[matter]

I am building 3 story wood frame residence on auger-cast piles, grade-beams and structural slab on grade. The foot print of the house is about 40’ x 50’. There are 4 rows of 18” auger-cast piles bored to bearing soils and have cages installed to 50% of bore depth. The grade-beams are designed as 20”w x 22” h and have 8 #7 rebar in them. 4 on top, 4 on the bottom wired in a normal manner. On top of the grade-beams will be a structural slab with a thickness of 7” to 9” in thickness. Some disagreement has arisen over plumbing and under-slab drainage. I’m looking for input/insight into how large and how many “buck-outs” (sleeves) can pass through the grade beams. The time is drawing close to pour and need to reslove this issue.

 

[JAE]

This is all by "feel" - but I'd keep all sleeves (I'm assuming they are horizontal and perpendicular through the beam) near the midspan of the gradebeam and centered in the vertical height of the beam.

I'd say a sleeve dia. of 10" would be appropriate.

I would not put any sleeves near where the piling are - keep them in the middle third of the span between piling.

 

[dicksewerrat]

At most you should only need a 4" ground run for the house and maybe two 4" lines for footing drains. Always center them on the grade beam. I think a 5" or 6" inside diam. sleeve would be enough.

 

[boo1]

The uder slad sewer drains are typically 3", dryer vent is 4". So dick's 6" appears a good number.