Here is another Main Floor and Kitchen Renovation in Mississauga, we also remodel their basement . There were some challenges with this project but that comes with the territory. We had to remove a load bearing wall that contained the plumbing stack that ran to the basement and some electrical. There was also a heating duct and cold air return that had to be relocated in the basement. There was also a partition wall that divided the dining room from the living room. All said and done the customer was very pleased. Please visit our website to learn more about us, check out our blog, and see our latest promotions.
Finished Basements: Looking at the New Concrete Floor
Welcome My Friends,
As we venture once again into the “Looking At” series from Finished Basements, about finishing your basement we would take a look at the New Concrete Floor. You could find more articles at http://www.finishedbasements.blogspot.com/ that would be worth your while reading and stocking up on very pertinent information.
Now that the foundation walls have been underpinned, the dirt floor have been leveled, the weeping tiles have been installed , the 4 inches of 3/4 in clear gravel has been poured and spread and the plumbing have been roughed in, it is now time to pour the new concrete floor.
Pouring the New Concrete Floor
You could order your concrete from either a Mobile Mix or a Ready Mixed truck. The Mobile comes with the dry product and it is mixed on site as it comes off the truck. The Ready Mix comes with the cement, sand , gravel and water already mixed together. The only draw back with the Mobile Mix is that you don’t get a consistent mix all the time.
Make sure that the concrete meets the Engineer specifications . Usually for a basement floor you will need at least 20 MPa @ 28 days, and about 5% to 7% air content. If the Engineer require a slump test, it should be done before the first load is poured into the basement.
To achieve the height of the finished concrete floor you could use a laser level to check the height to make sure its uniform. If you don’t have a laser level you could make short stakes from pieces of 2 x 2 material and pound those into the dirt floor to the desired height and check from stake to stake with a level. If you use the stake method you will have to pound the stakes below the surface of the concrete after you have the finished level.
You would probably need about 5 or 6 people to help with the pouring of the concrete floor. If the truck cannot back up and pour the concrete directly into the basement, you will need at least 2 people out side to deliver to the basement opening and 2 people inside to spread the concrete around. Have one person leveling the concrete.
The Leveling Process
Wait for the Concrete to cure for at least 24 hours before attempting to walk on it. Now that your floor has been poured and finished we could proceed to the framing and Mechanical stage.
Watch out for the next blog on the Framing Stage.
Underpinning your Basement
Jerome Sammy Finished Basements
This article deals with the underpinning of your basement foundation walls. Underpinning is the process used when you want to lower your basement floor. In the series of finishing your basement, we first looked at Finding a Contractor, Looking at the Basement Floor and Looking at the Basement Walls , you could find these previous articles at http://www.finishedbasements.blogspot.com/ There is also a side bar article on Installing a Pocket Door.
If you live in an older home and you find that the ceiling height in your basement is too low, you could lower the floor in one of two ways. One method is called the curb system where you don’t actually underpin the foundation walls but you add a concrete curb at the base of the foundation walls after you have excavated the depth that your require. Excavation is usually in 4 ft sections. Concrete curbs are usually done if you are not planning to lower your basement by more that 30 cm or 12 inches. The reason for this is that for every 7 inches you go down you will have to project out 10 inches from the foundation wall. Example, if you go down 14 inches you will have a curb projection of 20 inches into your basement. The only way you could achieve a ratio of 1:1 ,that is 7 inches down and 7 inches out, would be to hire a Geological Engineer to determine if your soil would be solid enough to withstand the weight of the house. You would then submit their report to the city when you apply for a building permit.
If you need help with any of these process you could contact us at http://www.fbscto.com
Things to Consider when Underpinning
There are a few items you will have to consider when you are planning on lowering your basement floor.
After you have had a structural engineer draw up a set of plans for underpinning your basement, and you submit your plans for approval form the city, you are now ready to proceed with the actual underpinning process.
Your basement walls will be marked off in 4 ft sections numbered 1, 2 and 3 to determine the different stages of the process and at the end of number 3 the stages will reoccur.
The excavation will begin but it must be done on a 45 degree angle of repose, or for every 7 inches you excavate 10 inches of dirt must be left against the foundation walls. The reason for excavating at the angle of repose is the pressure from the house does not actually go straight down, but is applies on a 45 degree angle that is why the dirt at the base of the foundation wall has to be wider as you excavate lower. At the bottom of your excavation point the dirt will now be wider than at the original height of the concrete floor. Never and I stress Never allow any one to ever excavate straight down, or your house will collapse or you will have major structural problems. If you follow these rules you should not have a problem.
After the initial excavation of the interior of the basement leaving the angle of repose, the process of actually underpinning the foundation walls will begin. Always remember never excavate into the angle of repose until you are ready to underpin that section.
There are two methods of underpinning: Under pouring and over pouring.
With the under pouring method the concrete is poured flush with front face of the existing foundations wall but is vibrated and under poured by at least 2 inches. After the concrete has cured at least 24 hrs , a non-shrink grout is dry packed into the cavity flush with the under side of the existing foundation footing.
The over pouring method is done with the new concrete projecting at least 3-1/2 inches out from the existing foundation wall and is over poured and vibrated to at least 4 inches above the existing foundation footings. There is no non-shrink dry pack involved.
Which ever method you use the excavation of the cavity is the same.
This is the process used to underpin the foundation walls of your basement. Make sure that you have all aspects of the underpinning process inspected by the city inspector. Have a structural engineer do your plans for the underpinning.
If you need any help or more information on the underpinning process do not hesitate to call 416-885-3987 .
Watch for the next Article on the New concrete floor.