At Renz landscapes we like to think of landscapes in three dimensions… just like in your home, a landscape has ceilings, walls, and floors which can be man-made and natural. A “wall” can be solid or allow a little see-through just for fun or be solid. It can take the form of a fence, a hedge or a more random, natural arrangement of different plants; creating visual screening and reducing noise. This page focuses on walls that are built with stone, brick, landscape timbers and man-made wall units… usually called segmental walls. A wall is a wonderful tool for creating different levels, terracing and retaining slopes in a landscape. A freestanding wall can visually separate spaces or act as a sitting wall perhaps along the edge a patio. Pillars can visually break up the expanse, provide contrast and highlight the end of a wall of the Outdoor lights placed in the pillars or under the seats of the wall can dimly light the surface of the patio and walls creating visual appeal.
Reasons for a Wall
Visual screening ~ Create a level area below or above the wall for different activities
To help make a slope above a wall less steep ~ To hold back a slope
To help mark or separate outdoor spaces and create a sense of enclosure
For visual interest ~ For sitting ~ Terracing… Creating multiple level areas to a space
Different Wall Characteristics
Height, length, and width along with variation within the same wall for a more contemporary look
Straight, curving, or a combination of both
Pillars provide interest, consider contrasting with the wall heights and materials
Be creative with pillar caps and play with the distance between pillars
Actual material ~ Color and texture ~ solid or open
Possible Wall Materials
Precast segmental walls ~ Brick ~ 6”x6” treated timbers ~ Natural stone veneer
Manmade stone veneer ~ Mortared natural stone walls
Dry stack (without mortar) natural stone ~ Concrete or stucco
A steep slope that held in place with boulders and plantings
Walls can also be a combination of materials including plants and wood
Special Considerations for Landscape Walls
Footings – In the Raleigh/Cary area it is not often that the ground freezes, but occasionally it can. Back in the 70’s and 80’s, the ground would freeze a foot deep, heave and cracking concrete footings if not poured deep enough. Generally more expensive, mortared brick, stone, and veneer walls need a concrete footing 6”- 12” deep so the footing doesn’t move, and the mortar between the bricks, stone and concrete block doesn’t crumble. The nice advantage, besides being cheaper, is materials like 6”x6” treated timbers, segmental walls, and dry stack stone walls can tolerate movement because there are not mortar joints. As a result, footings are simply 3”-6” of a compacted ABC material (gravel mixed with sand), if the ground moves, the wall moves with it.
Wall Caps – Are often a different material than the wall, and are couple of inches wider than the wall to provide interest.
Sitting Wall Caps – Generally set 20” to 24” above the patio and 12” to 20” wide for sitting.
Curved Walls – When constructing curved walls, make sure the wall material is capable of gentle curves, or turning tight different radiuses, so materials just aren’t .
Walls that Can Get Stained – With our red clays it is important to a fabric between the wall and the back fill so clay doesn’t work its way through the joints staining the wall.
Drainage – If water collects behind a wall, pressure and force can push a wall, causing it to lean or even collapse. It is important to divert as much rain water away from the wall and install geo-grid for walls over 4’. Gravel, holed pipes and weep holes move rainwater around or through the wall.