R404.1.5.3 Compliant Construction

[Francis Vineyard]

Figure R404.1.5(1) “FOUNDATION WALL CLAY MASONRY CURTAIN WALL WITH CONCRETE MASONRY PIERS”

The minimum spacing for piers to provide lateral bracing of curtain walls are provided in Table 606.9; this is not the 6 ft. spacing shown in Figure R404.1.5(1)!

“Anchorage shall be in accordance with Section R403.1.6, Figure R404.1.5(1)” This is the 6 ft. spacing requirement for piers with clay masonry.

Section R403.1.6; “Bolts shall be at least ½” in dia. and shall extend a min. of 7” into concrete or grouted cells of concrete masonry units.

So the code allows 4 inch CMU wall and does not specifically prohibiting anchor bolts in these walls?

Definitions:

MASONRY UNIT. Brick, tile, stone, glass block or concrete

block conforming to the requirements specified in Section

2103 of the International Building Code.

Clay. A building unit larger in size than abrick, composed

of burned clay, shale, fire clay or mixtures thereof.

Concrete. A building unit or block larger in size than 12

inches by 4 inches by 4 inches (305 mm by 102 mm by 102

mm) made of cement and suitable aggregates.

Glass. Nonload-bearing masonry composed of glassunits

bonded by mortar.

Hollow. A masonry unit whose netcross-sectional area in

any plane parallel to the loadbearing surface is less than75

percent of its gross cross-sectional area measured in the

same plane.

Solid. A masonry unit whose netcross-sectional area in

every plane parallel to the loadbearing surface is 75 percent

or more of its cross-sectional area measured in the same

plane.

 

[ICE]

So the code allows 4 inch CMU wall and does not specifically prohibiting anchor bolts in these walls?

The 4"CMU has eccentrically loaded the 6"CMU. I don't know if that's an issue but it would be a question that I would ask. That and are we sure that 4" is big enough.

We seldom if ever build foundations with CMUs. So I'm not the guy to ask.

 

[retire09]

CMU typically stands for concrete masonry unit.

Are you thinking these are clay masonry units?

 

[ICE]

CMU typically stands for concrete masonry unit.Are you thinking these are clay masonry units?

I figured that it's concrete. Clay would not work at all.

 

[Francis Vineyard]

CMU typically stands for concrete masonry unit.Are you thinking these are clay masonry units?

No . . . provided definition of clay to clarify Figure R404.1.5(1) in the code.

 

[retire09]

The detail you have provided is not using clay masonry. It is clearly calling for CMU (concrete masonry units).

 

[steveray]

R404.1.5.3 Pier and curtain wall foundations. Use of pier and curtain wall foundations shall be permitted to support light-frame construction not more than two stories in height, provided the following requirements are met:

1. All load-bearing walls shall be placed on continuous concrete footings placed integrally with the exterior wall footings.

2. The minimum actual thickness of a load-bearing masonry wall shall be not less than 4 inches (102 mm) nominal or 3-3/8 inches (92 mm) actual thickness, and shall be bonded integrally with piers spaced in accordance with Section R606.9.

R404.1.5.1 Masonry wall thickness. Masonry foundation walls shall not be less than the thickness of the wall supported, except that masonry foundation walls of at least 8-inch (203 mm) nominal thickness shall be permitted under brick veneered frame walls and under 10-inch-wide (254 mm) cavity walls where the total height of the wall supported, including gables, is not more than 20 feet (6096 mm), provided the requirements of Section R404.1.1 are met.

 

[Francis Vineyard]

Still compliant provided the 4 inch CMU does not exceed 4 ft. in height in accordance with R404.1.5.3 condition 4.

"R404.1.5.1 Masonry wall thickness. Masonry foundation walls shall not be less than the thickness of the wall supported,"

 

[David Henderson]

If the CMU has reinforcement in it looks good to go. Only two courses of 4". How ever I would question the location of the drain, has does the water below the perforated pipe and the bottom of the foundation drain?

 

[TheCommish]

drain seems unnecessary, the is no habitual or storage space below the slab

 

[JBI]

The drain may be for on-site conditions to keep the ground around the building stable, but TheCommish is correct. Backfilled on both sides, the drain is apparently not needed for the building.