# Okay to remove a few cinder blocks from my foundation?



## AU_Prospector (Apr 17, 2009)

I have a pest control company who wants to remove 6-8 cinder blocks from my foundation from the inside of my crawlspace to treat for termites.  This is necessary to directly treat the areas which are inaccessable from the outside because of my front porch and two back poured concrete patios.  

These would be permanant removals and allow future access termite inspection points for these areas.   Is this acceptable?  He would not be removing adjacent blocks.  Since the blocks are offset and not stacked, removing 6-8 on a foundation that is about 60 feet by 25 feet would not compromise structure right?  

He says this is old school but really correct to treat areas not directly accessable from outside and better than drilling through concrete front porch and back patios.  

Opinions from masons, foundation guys, cement guys etc please!


----------



## glennjanie (Apr 18, 2009)

Hello AU:
The technician is correct on drilling the patio or porch; it is very unsightly. If he is removing only one block per location, you could add a screened vent and the fresh air will deter termites as well. No, it will not affect the structure.
Glenn


----------



## AU_Prospector (Apr 18, 2009)

Glenn, thanks for the reply,

Let me clarify.  The blocks removed would be below grade.  He wants access to the soil  underneath of the slab porches.  He wants to probe along the outside of the foundation  and the underneath of the slab porches from this access point and apply pesticide.  He then wants to leave the block removed for future inspection access.

He keeps telling me this is a better way than drilling the slab porch.  He claims its common.  He also says it is a lot more work to do it this way, and if I insist on him drilling instead he will do that, but there is no guarantee that he will get a full termite barrier with drilling where as if he knocks out a few blocks he can get a continious wrap of termaticide around the foundation.  He only needs to do this in 3 places, front porch which is earth filled well above grade and the two back porches which are poured concrete at grade level.  The rest of the foundation will be trenched treated and filled. 

My concerns are excess moisture esp after a heavy rain, structure integrity, etc.  I am okay with the front porch, its the back patios where the blocks he wants to knock out are below ground level.


----------



## DaveyDIY (Apr 19, 2009)

AU_Prospector said:


> These would be permanant removals and allow future access termite inspection points for these areas.   Is this acceptable?  He would not be removing adjacent blocks.  Since the blocks are offset and not stacked, removing 6-8 on a foundation that is about 60 feet by 25 feet would not compromise structure right?



Will he warranty or pay for any needed repairs if something fails?

Only in 3 places, but 6-8 blocks?
Does that mean 2 blocks in each area?
Does he need to crawl under the house?


----------



## AU_Prospector (Apr 22, 2009)

Thanks everyone for your input.  I have researched and decided to use another company.  They will be drilling from inside of my crawlspace in the porch areas.  They will drill inbetween the blocks at the mortar joints and injecting "Termidor" to the outside soil and also inbetween the block foundation and the brick facing.  They will also trench the inside of my crawl at the foundation as well as the foundation piers and drill the perimeter of my concrete slab garage.  From my research Termidor is a communal contact poison that is spread through the colony even to the queen by the workers that travel through it.  It seems to be stable in the soil lasting 15 years or more.  I plan on taking pics and will post with a final update.  On the outside of my home they will drill the mortar joints of my brick facing and inject into the gap between the facing and the block foundation.


----------



## DaveyDIY (Apr 22, 2009)

I treated my last house myself
I had a crawl space so I was able to spray inside & out
I also put "poison" stakes into the ground 
I can't remember what they were
1/2 one year, 2nd 1/2 the next year

After that I put wood test stakes in the ground
I never saw any of the wood test stakes touched in the 7 years I was there

I sprayed my wood fence every year due to ants


----------

