Question
Hi,

I just did a pre-sale. THe hosue is being built by the builder. The fondation was poured and I some unusual things in the fondation and also saw some hug different in the height of the rockery and the lanscape.

Pony Wall: A 4 feet lumber pony wall is built over the concrete foundation to the floor of my house. Is it normal to built something like this on hilly terrains? So the otherr sides of the house has foundation walls upto the height of the floor however the rear wall fondation is raised using the pony wall.

Slopy Backyard: Initially I was told that I will have 25 feet deep yard but after the foundation was poured, now I am being told that I will ONLY get 18 feet deep yard (60 feet wide). There is a 3-4 feet rockery wall separating my yard to the neighbours. So right now, the height of the rockery is almost 4 feet below the landscape. If nothing is done, I will have 3 feet height and 2 feet deep slope between the rockery and the end of my backyard. The builders says the rockey hieght cannot be increased as it was engineered that way? Wihtout anymore trust in the builder, I am looking for POSSIBLE  solutions so that I have a levelled backyard without wasting any sq. ft area. I will really appreciate any suggestions of what can be done. Please let me know if I can provide you with additional information.

Answer
Hello,

Pony walls are used to reduce construction costs and they offer several advantages on hilly terrain. A high masonry wall may not be aesthetically pleasing and it is easier to install windows and run utilities with a pony wall.  However,a masonry or concrete wall is stronger but the thickness of the wall must increase as the height increases and corresponding to an increase in height there must be an increase in the size of the foundation. Buttresses and braces can also be used to make the wall less thick but also taller.

The pony wall may also offer greater insulation than a concrete or masonry wall when for instance,the pony wall is on other than a southern exposure. A concrete or masonry wall may be more desirable on a southern exposure because than in the winter it could act as thermal storage or a trombe wall.

Pony walls must be braced with plywood panels to enhance structural stability and to offer protection in earthquake activity. Pony walls over 4 feet high may require the services of an engineer.

Increasing the height of the rock wall will require a thicker wall and dry laid walls cannot be constructed as tall as mortared walls. About 4 feet would be about the height limit for a dry laid wall. The height limit is determined by your local zoning ordinances. I do not believe that the services of an engineer would be required for a wall up to 8 feet high. If the wall is a retaining wall,than the services of an engineer will be required for any height over 4 feet.

You may also be able to increase the height of the wall by installing a wooden fence on top of the wall. On a slope,the wall may have to be tiered to compensate for the grade change.

Leveling the yard will require regrading by cut and fill (cut the higher slope area and fill the low area) but that will lower the grade around the foundation of your house and may require the rock wall to need rebuilding. Good luck. Let me know if I can be of further help.

Mark Harshman
http://www.mahdrafting.com
Email: [email protected]

http://www.allexperts.com/ep/724-104627/Landscaping-Design/Mark.htm