Basic Concrete Finishing Knowledge for Tacoma, Washington

   Planning and Preparation

  Before you begin your project, it is important to properly  plan and prepare. Proper planning will save time in the end, and helps  to assure your satisfaction with the product. If you are unsure of how  much concrete you need or if the area is suitable for concrete,  give Cascade Mobile Mix Concrete & Line Pumping a call today at  253-847-9119. Our staff is experienced in all types of concrete pouring  situations and will answer all of your questions. 

Thickness

For common household projects - driveways, walkways, and patios – 4  inches thick should do the trick. Thicker concrete (i.e. 6" is  recommended for heavy-duty use or heavy vehicles) It is recommended to  use a ¾ minus crushed gravel compacted base. You can get a compactor  from a rental equipment store. Drainage industry standard calls for a  slope of ¼ inch per foot away from structures. Some projects may be able  to use ⅛ inch slope. 

Excavation

While taking care to only dig as deep as necessary (keeping an eye out  for power lines; if you are unsure where lines are, call your utilities  for a locator), ensure you remove tree roots, leaves, wood and any other  organic matter in the desired area. 

Isolation

Install expansion joint material anywhere concrete will come into  contact with existing slabs, steps or buildings. The expansion joint  should reach the bottom of the slab; this ensures the new slab will be  separated from existing structures.

Now that you have your planning down, we suggest you review our Concrete Calculator to determine your exact needs. 

Specifications

Specifying the correct mix for your job can be the difference between  long-term satisfaction and disaster. Concrete specifications consist of  strength (PSI), slump (thickness) and chemical additives. 

Strength

Concrete Exposed to freezing and thawing temperatures should have a  compression strength of 3000 psi and have at least 5% entrained air (+/-  1.5%). Air entrainment allows for the expanded water when frozen to  travel into the air voids created by the air additive. Without the air,  concrete is at risk for cracking. 

Slump

For our environment, we recommend a slump of 4 inches (+/- 1"). Note: a  slump greater than 4" may prolong the time you have to wait before  finishing, particularly in cool weather. It will also increase the  tendency for shrinkage cracking. 

Compaction

Will ensure your slab won't settle or vary in thickness, make sure to compact the soil/gravel base in the desired area. 

Forming

Take care to stake your forms securely to the ground, while paying close  attention to the slope (for proper drainage). 2x4s are perfectly  adequate for use as forms; though make sure you have the desired  thickness (usually 4") available at the edges. 


Chemical Additives

In addition to air entraining admixtures, chemical additives may be used  to accelerate or retard setting, reduce water or plasticize the  concrete. 

Cascade Mobile Mix Concrete & Line Pumping's concrete is a high-quality concrete and we run a plasticizer in our concrete unless requested not too. 

Our Guarantee is in Concrete