© 2009 by DIY In A Hour.com. All rights reserved. We welcome your comments and suggestions. Information provided "AS IS". You may freely link to this site, and use it for non-commercial use, subject to our terms and conditions of use. Please view our privacy policy.
Was this post
helpful to you?
helpful to you?
What Does It Cost?
edit
Foundations Explained
Most homeowners do not undertake extensive foundation projects themselves, but many are able to correct minor defects or build the foundation for a room addition. Even if you are not planning a project that involves any foundation work, you should have a basic knowledge of what your foundation does and how to recognize serious problems. It is important to keep in mind the main function of a foundation when you are inspecting it, analyzing problems, or planning extensive new work. These functions are important in determining the design details and the materials that will be needed.
.jpg)
The foundation carries the weight of the house to solid ground. Solid ground means undisturbed soil that is at least 12 inches below grade, and much deeper for special conditions, such as soils that are subject to much freezing or expansion or soils on steep grades. Spread footings distribute the weight, and in some cases deep piers carry the weight as far as bedrock or more stable soil.
The foundation keeps the wood structure of the house above the ground. Foundation materials, such as concrete, masonry, and pressure treated lumber, must hold any other wood at least 8 inches above grade to prevent decay and insect damage.
It provides a level and stable base for the house. The foundation compensates for an uneven building site and should be constructed to counteract any tendencies of the ground to settle or heave.
The foundation provides an anchor from wind and seismic forces, which can move a house and damage it. A house needs more than it's own weight to hold it in place. The mass of the foundation and the fact that it is buried in the ground are what hold a house in place under stress - as long as the house is secured to the foundation and is tied together well itself.
The foundation keeps the wood structure of the house above the ground. Foundation materials, such as concrete, masonry, and pressure treated lumber, must hold any other wood at least 8 inches above grade to prevent decay and insect damage.
It provides a level and stable base for the house. The foundation compensates for an uneven building site and should be constructed to counteract any tendencies of the ground to settle or heave.
The foundation provides an anchor from wind and seismic forces, which can move a house and damage it. A house needs more than it's own weight to hold it in place. The mass of the foundation and the fact that it is buried in the ground are what hold a house in place under stress - as long as the house is secured to the foundation and is tied together well itself.
It keeps moisture out of the crawl space or basement. The foundation itself does not actually do this; lack of moisture depends on waterproofing materials and an effective drainage system. The foundation does give some protection and it provides a stable structure on which to install waterproofing materials.
Find How-to Articles, Projects, and Expert Advice.
In A Hour.com
Photo illustration courtesy of visual dictionary online
Preventing damage. Major foundation and structural damage are symptoms caused by other problems. In some cases the problem is one of poor foundation design or a failure of the soil bed. Most often, however, the symptoms are the result of simple conditions that any homeowner can correct. The following steps will help prevent damage from occurring or cure problems that are still minor.
Grade the soil around the foundation so that it slopes away from the house 1/2-inch per foot for at least 30 inches.
Fix gutters and downspouts so that water is carried away from the foundation, ideally 10 feet or more.
Dig trenches or install diversion drains upslope from the house.
Install waterproofing material and a drain system around a badly leaking foundation.
Patch visible holes or cracks
Inspect periodically for mud tubes, sawdust, or other evidence of termites or powderpost beetles.
Install anchor bolts to connect the mudsill to the foundation.
Remove all dirt that is within 8 inches of any wood.
Types of foundations. There are three basic types of foundations. They are:
Perimeter. A perimeter foundation creates a crawl space under the house. Most perimeter foundations are made of poured concrete or concrete block, although it is not unusual to find brick foundations in older buildings. Separate piers support girders and other concentrated loads within the perimeter.
Slab. A slab built on grade functions as both the foundation and floor system. It is an economical type of foundation but can only be built in areas where soil conditions will permit construction. The slab must have deep footings under all the perimeter and bearing walls, and should always be at least 8 inches above grade.
Basement. A basement foundation has higher walls than a perimeter foundation. It is built on a footing and has separate footings for support columns. The basement floor usually consists of a concrete slab poured after the footings and walls are completed.
Grade the soil around the foundation so that it slopes away from the house 1/2-inch per foot for at least 30 inches.
Fix gutters and downspouts so that water is carried away from the foundation, ideally 10 feet or more.
Dig trenches or install diversion drains upslope from the house.
Install waterproofing material and a drain system around a badly leaking foundation.
Patch visible holes or cracks
Inspect periodically for mud tubes, sawdust, or other evidence of termites or powderpost beetles.
Install anchor bolts to connect the mudsill to the foundation.
Remove all dirt that is within 8 inches of any wood.
Types of foundations. There are three basic types of foundations. They are:
Perimeter. A perimeter foundation creates a crawl space under the house. Most perimeter foundations are made of poured concrete or concrete block, although it is not unusual to find brick foundations in older buildings. Separate piers support girders and other concentrated loads within the perimeter.
Slab. A slab built on grade functions as both the foundation and floor system. It is an economical type of foundation but can only be built in areas where soil conditions will permit construction. The slab must have deep footings under all the perimeter and bearing walls, and should always be at least 8 inches above grade.
Basement. A basement foundation has higher walls than a perimeter foundation. It is built on a footing and has separate footings for support columns. The basement floor usually consists of a concrete slab poured after the footings and walls are completed.
related video: foundations explained
The foundation to your home is explained and discussed.
