Building Homes or Extensions/Walls& windows


I am having an extention to my house and I noticed that when they put 8' concrete blocks, some of the have holes between them.
I aksed my builder to fill them in with cement, he said that is ok, no problem, you will still have outside a brick vaneer too. I am afraid of water getting in, insects etc if the holes will be left.
Also I aksed my architect to put the headers on the windows of the first floor to make them strong enough to support the second floor. I just noticed that blue print has support for new windows but there is no support for the existing windows. What I should do? Please advise.

Nushaba, I'm a bit confused about what you have.  I think you are telling me that the new exterior walls are 8" cement block that will have a brick veneer.  If it had been my design, the block walls would have been mortared and struck on both faces - there would be no voids in the mortar joints.  In addition I would have waterproofed the outside of the block, usually done with tar based product; and added rigid foam insulation between the block and brick along with the dead air gap.

As to the headers, I need to assume that the original structure had headers over the existing windows so they should not require additional work.  If there is any doubt, check with the architect.

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Dan Griffin


I can answer almost all questions related to the total construction process. My expertise is in commercial construction, though I can field most any residential question. I have hands on experience in concrete, heavy equipment, masonry, all phases of carpentry, interior finishes, and I am fairly strong in mechanical and electrical.


I have over 20 years experience as a commercial carpenter and commercial construction superintendent. I have another 20 years experience in facility management for a major school district.

My favorite hobby for he past 12 years has been singing bass in a The OkChorale men's barbershop chorus and the Mature Moments quartet.

I hold a Bachelor's degree in English and Math. I have completed many continuing education hours in the building trades. I hold a Master Carpenter card from the AGC, Associated General Contractors.

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