QA

Quick Answer: How To Lay Concrete Block Walls

Should you wet concrete blocks before laying?

Do not wet the blocks before installing them. Wet blocks expand, then shrink when they dry. If it rains or rain threatens, cover the blocks.

How deep should footings be for a concrete block wall?

Normally a foundation wall with seven rows of blocks will be 24 inches wide and 12 inches deep and should have a footing 30 inches below grade.

Should concrete blocks be filled?

Considering everything, filling your cinder blocks isn’t exactly necessary, but it is completely safe, assuming you don’t add dirt in it. Filling cinder blocks can help you make the structure sturdier or improve insulation, while a mix of gravel and sand can actually help you achieve both.

Do you need rebar in a block wall?

Wall Size. A freestanding garden wall or block privacy fence will require less reinforcing than a basement or other load-bearing wall in a house or other building. An 8-foot-high wall will obviously require more rebar than a 4-foot wall. Very short walls, under 4 feet and laid with mortar, may not require any rebar.

How much space do you need between concrete blocks?

Lay out the block, making sure to leave a 3/8 inch gap between the blocks to allow for the vertical mortar joints (i.e., a typical 8x8x16 block is actually 15-5/8 inches long and 7-5/8 inches high to accommodate the mortar joint).

How soon can you lay blocks on concrete?

The footing should rest on firm soil (preferably undisturbed) set below the frost line. Check with your local building department for the exact depth of the frost line. Allow the footing to cure at least seven full days before beginning to lay the block.

Are poured concrete walls cheaper than block?

Is a poured concrete foundation cheaper than a block wall foundation? Usually, the cost of construction varies from place to place. But as a matter of fact, poured walls cost about 20% less than the block foundation walls.

How deep should a foundation be for a block wall?

All footings should be a minimum of 150mm (6″) in depth, with the bottom 350 – 400mm (14-16″) below ground level on most soils. For clay soil however, thicker and deeper footings should be used.

How much concrete do I need to fill a block wall?

Fill Volume for Various Block Wall Thicknesses Block Wall Thickness Blocks Filled per Cubic Yard Concrete/Grout per 100 Square Feet Wall Area 6″ 120 .93 yd 3 8″ 100 1.12 yd 3 10″ 80 1.3 yd 3 12″ 65 1.73 yd 3.

How much does a pallet of concrete blocks cost?

One pallet of cinder blocks costs $115 to $225 on average. A pallet of cinder blocks weighs 2,500 to 3,250 pounds. A standard pallet holds 70 to 90 cinder blocks.

What is the difference between cinder block and concrete block?

Cinder blocks are hollow rectangle-shaped structures usually made of concrete and coal cinders which find use in construction sites. Concrete blocks often, on the other hand, are flattened constructs made of steel, wood or cement.

How high can you build a concrete block retaining wall?

Most retaining walls, whether load-bearing or not, average between 3 and 4 feet in height. As a general rule, you do not want to build any sort of structure over 4 feet in height without including some type of structural support within.

How hard is it to lay concrete blocks?

While some might find laying concrete blocks down an easy task, it can be overwhelming for beginners. It requires time and a good bit of supplies. If this is your first time, plan the task out with a friend. It is essential to use materials that both suit your project and the land you build on.

Can you lay blocks without mortar?

QUIKWALL® Surface Bonding Cement (SBC) now makes most block construction possible without using mortar; it’s literally a “stack and stucco” project. A single coat on dry-stacked block gives a handsome stucco finish and provides greater flexural and impact strength than mortar with less expense.

How much mortar do I need for cinder block wall?

Three bags of mortar are estimated for every 100 block, therefore 6-3/4 bags of mortar are needed ((225 block x 3 bags mortar) / 100 block = 6-3/4 bags of mortar).

Why are there spaces between the concrete blocks?

To allow for the vertical mortar joints, leave a 3/8 inch gap between the blocks and lay out the block. A reference line can be created by snapping a chalk line on each side of the wall.

How high can you build a block wall?

A: You are correct. A 4-inch-thick, nonreinforced concrete masonry screen wall should not be built higher than 6 feet, 8 inches unless it is supported laterally in the horizontal or vertical direction every 6 feet, 8 inches.

How do you level concrete cinder blocks?

How To Level Concrete Blocks Select hard Wobble Wedges of the appropriate size (see 4 Interlocking Sizes). Set a level string line on both sides of the block as a guide. Press or lightly tap a Wobble Wedge under both sides of the blocks as needed to bring them squarely up to the guide line.

Does a 2 foot retaining wall need drainage?

These walls need a drainage system regardless of the wall height. If there are poor draining soils such as clay behind the wall, there needs to be drainage incorporated the wall system. Clay when wet is very weak, so it is essential to provide a way for water to escape from behind the wall.