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Why should I use Allan Block for my landscape project?
For more than 15 years Allan Block has made it easy to Plan, Design and Build landscape walls of distinction. Allan Block has a solution for almost any landscape application. View the Allan Block publications Landscape Lifestyles and Landscape Design Guide for some great ideas.

How high of a wall can I build with Allan Block?
Allan Block walls have been built over 40 feet in height (12.2m). More practical landscape walls, 6 feet in height and under (1.8m), are made easy by following the Allan Block publication Landscape Design Guide or the Allan Block Installation Guides.

Do I need a concrete footing for the blocks?
No. Allan Block is designed to sit on a compacted granular base. This saves time and money while providing a solid base for the blocks. See the Landscape Design Guide for the recommended depth and width of base for your wall.

How long will Allan Block last?
We know that standard concrete building blocks made in the 1950s using a similar process are still performing in building structures around the world. With the improvements in technology used today, we believe Allan Block units will last a lifetime.

Are the blocks safe for the environment?
Yes. The Allan Block units are made using natural, raw materials and are safe to use in the environment. No harsh chemicals such as those found in treated timber are in Allan Block.

Can I cut an Allan Block?
Yes. Blocks can be easily cut using common tools to give your wall a professional appearance.

How does Allan Block stack up?
Allan Block is a dry stacked system; no mortar or glue is necessary. The blocks are formed with a unique, raised front lip that acts as a guide to automatically setback and interlock the blocks, as they are stacked.

Why do the blocks setback as they are stacked?
Allan Block units setback as they stack to improve the stability and performance of the wall. They are designed with an automatic setback of 3, 6, or 12 degrees of "lean" into the hillside. The top lip and bottom notch combine to form the automatic setback. No measuring is necessary. Block setback is noted on all Allan Block publications.

How much does Allan Block cost?
Allan Block cost varies depending on the style of wall you choose. Allan Block walls are competitive with timber and stack rock, while costing up to 30 percent less than walls requiring concrete footings. Call a Bergman Concrete today for a price quote. 902-832-0506

How does the cost of Allan Block compare to other landscape walls?
Consider the options: landscape timbers, stacked rock, poured concrete or mortared solutions. Allan Block is cost competitive with all these options.
• Consider the value of Allan Block:
• Will not rot or decay - lasts a lifetime.
• Does not require any special fasteners such as nails, pins, or
clips.
• Dry stacked - no mortar and no concrete footing.
• Curved or straight walls are virtually the same cost.
• Different looks, colors and styles are achievable with very little
cost difference.
• Allan Block makes it easy - A complete solution.

How easy are the blocks to handle?
The hollow core, raised front lip and wing back design of the Allan Block system makes them very easy to lift and stack. Blocks are available in different sizes, styles and weights. Ask your local Allan Block Dealer for a demonstration on the ease of building with Allan Block.

How do I care for my Allan Block wall?
Allan Block walls are virtually maintenance free when properly built. The AB How-To Series - Care & Maintenance of Allan Block Walls has simple solutions to common maintenance related concerns.
What do I need to know as I plan my landscape wall?
Review the Landscape Design Guide as you consider soils, slopes, surcharges, block style and wall heights in the planning of your landscape wall project. The AB How-To Series of publications are another helpful resource that target more specific applications and details.

How do I choose the right Allan Block product for my project?
Allan Block has a size, weight, and style that are right for just about any landscape. Use the “AB Product Selection Guide” in the Landscape Lifestyles publication to choose the style that best complements your project. See the AB Collections Product Sheets for all the product specifications and use the Landscape Design Guide as your guide to planning, designing and building your landscape.

Can I build on uneven or sloping ground?
Yes. Allan Block easily adapts to a sloping base. Starting at the lowest area, simply step the blocks up as you build into the slope. See the AB How-To Series - Top and Bottom of Wall Details for reference.

Do I need a permit to build a wall?
Contact your local building code department to see if building permits for landscape retaining walls are required in your area.

Can I build a wall in water? (ie: A pond or a lakefront?)
Yes. Allan Blocks design flexibility makes it the perfect choice for water front applications even in areas where freezing is a concern. There are special considerations that your local Allan Block Dealer can help with.

Can I plant a garden or landscape around the blocks?
Yes. Planting or landscaping in the block cores or behind the blocks is easy and environmentally safe. Allan Block does not leach any harmful chemicals that could affect your plants or shrubs. A drip irrigation system can even be built into the wall during construction.

Can I build a fence on top of a wall?
Yes. Fences can be built in the blocks hollow core or behind the wall. The wall may have to be reinforced to support the wind load from the fence. Call your Allan Block Dealer for help.

How many blocks do I need?
The number of blocks needed depends on the unit size of the Allan Block you have chosen and the size of your project. Typically by multiplying wall height by wall length you can get a square foot area. Divide the area by the unit size to get a rough estimate. There are quick estimating guides on the AB Product Sheets for your reference and your Allan Block Dealer is also trained to help you calculate your requirements. Be sure to include corners (left hand & right hand) and caps if required for your project.

How much do the blocks weigh?
Allan Block is available in a variety of different weights from under 30 lbs (14kg) to over 75 lbs per unit (34kg). Heavier blocks are typically designed for taller walls. Unique to Allan Block is the blocks hollow core that makes them easy to lift and stack. Allan Block unit weights are listed in several Allan Block Publications.

What tools will I need?
There is a suggested tool list in the Landscape Wall Design Guide. Tools required depend on the size of the job. Small walls may only require some basic tools such as a shovel, rake, wheelbarrow, small sledgehammer, 3" chisel, level and hand tamper. Larger or more detailed walls may need additional equipment such as a plate compactor and a diamond blade saw for cutting.

Discuss your project with your Allan Block Dealer for advise on tools and equipment to make your project easy. Some Allan Block Dealers rent tools and have cutting services for your convenience.
What do I need to know as I design my wall?
Consider style and function as you initiate your landscape wall design. Review the Landscape Design Guide as you consider stairs, terraces, and finishing details.

What are my color and style choices?
From the natural antique appeal of Europa, to the marbled color of Ashlar, to the clean look of the AB Collection, Allan Block has colors and styles that complement any landscape. See the Landscape Lifestyles publication and choose the look that's right for your project. Call your local AB Dealer to confirm colors and styles available in your area.

Can I design and build stairs?
Yes. Stairs can be designed and built using curves or corners in a number of different styles. See the Landscape Lifestyles and Landscape Design Guide for some great ideas on stair design then see the AB How-To Series - Stairs & Steps for detailed design and construction details.

How tight a radius can I design and build?
Minimum curve radiuses are based on the block size, and are noted on the AB Product Sheets.

What are terraced walls and how do they work?
Terrace walls tame a slope by building two or more low walls rather than one tall wall. Once the lower wall is built, the next wall can be constructed, leaving an area in between the walls for landscaping or planting. Ask Your AB Dealer for design assistance and see the AB How-To Series - Terrace Walls for more design and construction details.

How do I finish off the top of the wall?
Unique to Allan Block is the raised front lip on the block that provides a perfect edge for landscape mulch, decorative rock or AB capstones. See the Landscape Design Guide or How-To Series - Top & Bottom of Wall Details for more ideas.

What does the term "Gravity Wall" mean?
A gravity wall is a wall that relies on its own weight to hold up the soil behind it. The weight of the blocks and the granular fill in the block cores, combine to become the weight of the wall. See the AB How-To Series - Reinforced Walls for a more detailed, yet simple explanation of a gravity wall.

What does the term "Reinforced Wall" mean?
A reinforced wall is a wall that uses layers of reinforcement grid to tie the blocks and soil behind the blocks together to form a larger and heavier wall. See the AB How-To Series - Reinforced Walls for more detailed yet simple explanation of a reinforced wall.

How do I know if I need reinforcement?
The need for reinforcement depends on the weight the wall is holding back. See the pre-engineered "Soil Reinforcement Chart" in the Landscape Design Guide to see if your wall needs reinforcement

What is AB Reinforcement Grid?
AB Reinforcement Grid is a high strength polyester mesh that is coated with a protective black film and is conveniently available from AB Dealers. See the AB How-To Series - Reinforced Walls for more information about AB Reinforcement Grid and its use.

Can I use lighting in the wall?
Yes. Lights built into the wall can provide a beautiful ambience to patios or add safety lighting along stairways. Use lighting fixtures designed for outdoor use and follow manufacturers instructions.
How do I find a professional Certified Allan Block Contractor?
Your Allan Block Dealer will be able to recommend a Certified Allan Block Contractor.

How do I get started?
After a quick review of your plan, the Landscape Design Guide and helpful "How-To" notes, you should be ready to start building your wall. Here is a short checklist: Order materials, gather tools, prepare the site and layout the wall locations and dig the base trench (starting from the lowest point). Follow the step-by-step installation guide in the Landscape Design Guide and don't hesitate to call your Allan Block Dealer should you have any questions or need some additional help.

What are some good layout ideas?
• Use a garden hose to layout a smooth curve or as a "water level" to help
determine grade changes.
• Use a 3-4-5 triangle to build square from another structure.
• Mark utilities with a wooden stake or paint.

What kind of material should I use for the base?
A good base material is a crushed stone ¼" to ¾" in size. This material compacts well and makes it easy to level the base block.

Is compacting the base important?
Yes. A compacted base provides a solid foundation to build on and will not allow water to saturate the base material leading to a potential weakening of the base.

Is leveling the base block important?
Yes. The base blocks need to be leveled back to front and side-to-side.

Why should I bury some of the base block?
Partial burying the base block reduces the risk of erosion and potential undermining of the wall due the base being exposed. Bury a minimum of 1" per foot of wall height.

Do I need to stack in "running bond"?
No. "Running bond" refers to a pattern where the seam between any two blocks falls exactly on the center of the block below it. Perfect running bond is not essential for Allan Block walls. We recommend a minimum average offset of 3 inches. You can insert half blocks as needed to help maintain some staggering.

What kind of material should I use to fill the blocks and for the drainage behind the blocks?
You can use the same material as the base (¼" to ¾" crushed stone) although some contractors prefer to place ¾" clear crushed / angular stone because it is easier to work with.

When do I need to backfill?
Backfill every row of block you stack - and check your wall for level at the same time. Backfilling more than one row at a time may cause the wall to lean forward.

How do I use AB Reinforcement Grid?
AB Reinforcement Grid simply rolls out along the wall. Follow the installation instructions printed on every roll of grid.

How do I end a wall?
Ending a wall into a hillside, stepping down into grade or a combination of both are options to ending a wall. See the AB How-To Series - Finishing Options for some great, pro-finish details.

How do I build corners?
Outside corners use the Allan Block 90 degree corner units. AB corners come in a pairs of a left and a right hand unit. As the left and right hand units are alternately stacked they form a strong interlock.

Inside corners are formed using standard Allan Block units. Part of the top lip on the blocks is removed so the blocks can alternately over lap on each other to form a strong interlock. See the Landscape Design Guide for details.

How do I make a corner cap?
Corner caps are typically miter cut with a saw on the job. Some Allan Block Dealers may offer cutting services or pre-cut corner caps for the convenience of their customers. (Allan Block does not manufacture a "corner cap unit") See the AB How-To Series - Capstones Details & Cuts for ideas on how to cut AB capstones.

How do I cut the blocks?
When it is necessary to cut a block use a saw with a diamond tipped blade. A better question is to ask is "how do I avoid cutting the blocks?" Good planning by way of project design and use different yet compatible sizes during construction is not only a time saver but also a "cut saver".

Do I need an engineer?
Generally, Allan Block recommends the use of a licensed engineer on projects with taller walls or unusual site conditions. Local building codes may require the use of a licensed engineer for walls above a certain height. Our design charts and tables provide generalized engineering solutions. Each retaining wall site is unique, however, and specific evaluation will provide the most accurate solution.