Building Homes or Extensions/construction


Good day
When compacting concrete (vibrating) can you give me an average of how much additional concrete one has to add. For example is 1%, 5%, 10% extra required after compaction.
Just looking for a general figure (an approximation) of what percentage extra concrete has to be ordered in an estimate due to loss from compaction (vibration)

Hi Sam,  I don't think I ever consider settling when ordering concrete.  Depending on the quality of the form work I figure cubic feet and then convert to cubic yards usually rounding up to the nearest ten yard increment if it is a hundred yards or more.  If the foundation or whatever is earth formed I generally add another 10% to be safe.  Most times we hold our orders to the nearest full load and do a measure and a call back for the remaining bump.  Due to forms shifting and expanding, the nominal size of masonry and other factors, you aren't going to be able to pinpoint down to the teaspoon exactly how much concrete you should order.  If the concrete plant is relatively close keep your estimate tight and order back, if the batch plant is constantly overbooked or over an hour away you might take the more aggressive approach and order extra.  It's always good to have enough and if you have other smaller projects nearby like sidewalks or curbs etc.  you can always find a place for excess concrete.

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Bruce E. Johnson


I can answer any construction related question in regards to carpentry, concrete, drywall, masonry, structural elements of any type of building, residential or commercial. Interior or exterior.


Custom Commercial and residential buildings. Churches, theaters, schools and auditoriums. Most recently I am working with the Catholic Church on several design build committees. I have a website related to scheduling and project supervision. Although my expertise is more related to multimillion dollar commercial, educational and theatrical projects my generous credentials in residential and remodelling construction make me a viable source of information regarding all forms of building questions.

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