October 20, 2017

Retaining Wall Construction: Do I really need a permit?

Are you thinking of building an Allan Block retaining wall, fence, or courtyard patio? If so, you may be wondering “Do I need a building permit to do this job?” or “How tall can I build this wall before I need a permit?” You are not alone. This is a very common question when it comes to building patios, fences, and retaining walls.

Unfortunately, there is no one simple answer to either of these questions. Every state, city, county, and municipality is varied in what they require a building permit for. Below is an excerpt from the City of Saint Paul on what they require a building permit for. As you can see the city requires a permit for any fence application. When building a retaining wall over four feet tall a building permit is required. A simple Google search ought to turn up similar documents for your local city. You can’t find your local permit requirements via the internet? Try calling your local city offices. Ask to speak to somebody in the Department of Safety and Inspections. Somebody in their office should be able to provide you with your local permit requirements for any and all applications.

Once you’ve sorted out whether or not you need a permit, you might want to consider hiring an AB Certified Contractor. Our Certified Contractors are well versed in how to install all of our AB Products. They are well versed in both our Best Practices and Commercial Installation Manual. This will ensure whether you’re building an AB Fence, Courtyard, or Retaining Wall project it will stand the test of time for many years.

October 13, 2017

How Do I Add a Drain Pipe to My Retaining Wall?

Drain pipes within a retaining wall are designed to remove incidental water that may collect at the base of the wall.  The primary water management happens above and below the wall where grading and surface materials are designed to efficiently remove water before it saturates the retaining wall system.  
A toe drain pipe should be located at the back of the wall rock behind the wall as close to the bottom of the wall as allowed while still maintaining a positive gradient for drainage to daylight, or a stormwater management system.  

Level Sites

For site configurations with bottoms of the base on a level plane it is recommended that a minimum one percent gradient be maintained on the placement of the pipe with outlets on 50 feet (15 m) centers, or 100 feet (30 m) centers of pipe is crowned between the outlets.  This would provide for a maximum height above the bottom of the base in a flat configuration of no more than 6 inches (150 mm).

Drain Pipe

You can use rigid or flexible drain pipe.  For rigid pipes position the holes a down.  Allan Block does not require that toe drain pipes be wrapped when installed into base rock complying with the specified wall rock material.

Routing Water

On sites where the natural drop in grade exceeds the one percent minimum, drain pipes outlets should be on 100 foot (30m) centers maximum.  This will provide outlets in the event that excessive water flow exceeds the capacity of pipe over long stretches.

Raised Vents

When the drain pipe must be raised to accommodate outlets through the wall face, refer to the Allan Block Spec Book.

October 6, 2017

How do Allan Block Retaining Wall Blocks Stack?

Today, we are going to explain how and why Allan Block retaining wall blocks stack together.  The basis of stacking blocks that lock together give a wall system the structural component and Allan Block is no different.  Most Allan Block’s consists of a front  lip and bottom notch.  As you place a second block on top of the first, the bottom notch of block #2 (top block) interlocks with the top notch of block #1 (bottom block) which engages the system.  This type of system is the same for ABCollection, AB Europa, and AB Aztec collections.  AB Fieldstone has the same type of interlocking system, but the anchor unit has a rear lip and notch system.  These blocks stack the same as all other blocks, but the back lip of the top block (#3) interlocks with the notch on the bottom block (#4).  All Allan Block products lock together with a lip and notch system, which makes Allan Block one of the easiest products to use.

September 29, 2017

How do I Build a Curve with AB Courtyard?

The AB Courtyard blocks come in 2 shapes, the AB Dublin and the AB York blocks.  The AB Dublin blocks work great for straight sections with the AB York used for straight and curved sections.  The blocks come in angles as part of the system with the AB York having 2 different sizes on each side of the block which in turn makes it perfect to build curves.

By placing the blocks with the longer side together will build the curve automatically.  No need for cutting or modifying blocks.  Larger curves can be created by blending the AB York and the AB Dublin together in patterns to create flowing curves.  There are several videos, installation details and patterns available to show how to build with AB Courtyard to ensure you have all the resources needed to complete your project. 

September 22, 2017

Can I Build Stairs Out of Blocks?

Blocks, more specifically - retaining wall blocks, are a great solution for building stairs outdoors without compromising style: You can build stairs either curvy or straight, make them one continuous line or drop in a turn or a landing to break up the line and add character to the design.
Drop in a turn and a landing
 to break the stair line
Break up long sets of steps
with landings
Add switchback curves
to meander up the hill

If you are already building a retaining wall, you can easily integrate stairs into your design.
Curved steps with corners parallel
to the retaining wall
Curved steps parallel
to retaining wall
Curved steps into
retaining wall face

Take the time to build it right from the start. Follow a similar principle of “measure twice and cut once”

Spending time to plan and learn the techniques before you start your project will go along way. Read the detailed stair construction instructions on Allan Block website, and watch this video to get a visual on what this process entails. 

This will help avoid issues and errors that can potentially lead to your project failing. Not to mention the time and money you save, when you build your wall correctly.
Here are the steps to building stairs with Allan Block:

  1. Calculate the number of steps your stairs will have.
  2. Determine the Stair riser locations. Excavate according to the rise and run.
  3. Excavate the base trench and stair location
  4. Install base course
  5. Install first riser
  6. Backfill and compact
  7. Repeat these steps for each additional stair riser needed to finish your stairs.
Once all stair risers are in place, install the tread material you selected to finish your stairs.

If you are using AB Fieldstone, you can build the stairs using the long anchoring unit for quick and easy installation.

Always check the local building codes before starting construction. You can also get help from your local Allan Block Dealer.