Hi: I did read the posts I had found for simliar topics. Someone mentioned using a Mapei sealant rather than a moisture membrane. The concrete that I will be applying to the existing concrete slab will be a thickeness of 3-1/2″ to 6″ to level the existing concrete and to allow for a recessed area for a brick floor.
I would like opinions if I should use an adhesive liquid sealant to adhere the new slab to the existing, or should I float the slab with a moisture membrane of 10 mils?
design
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Replies
Hello fellow posters:
I found a manufacturer that can combine a waterproofing and bonding agent. I thought I would come post it here for others that may be considering the same thing.
Krystol T1, a cementitious concrete waterproofing agent can be combined with an acrylic bonding agent to seal the existing slab and act as a bonding agent for the new slab. The products are produced by Kryton.
Cler
I'm curious about the overall scope of the project. Exterior?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Hi Piffin, the project consist of an addition and renovation to an existing residence. It was a house that my dad had designed, and the new owners come to me to renovate the carport. The existing slab of the carport was pitched to allow for run off of any condensation or rain water. The slab was designed with a 6 mil moisture membrane (visqueen). Just to be safe while leveling the existing slab, I wanted to seal the concrete before adding more concrete.
I also have that tricky lil' area where I am adding on, but I believe I have it all covered with a sawcut control joint, and so much more ;). I'm an Architect Intern, but my boss told me I could loose the intern and be a drawing coordinator :).
I'll keep up with the board, b/c I may be able to help some of the other posters, unless Architects are disliked in here :).
Cler
Edited 2/3/2005 7:32 pm ET by Design
you do not want to seal the old slab. the new slab needs to bond with the old. Moisture is not going to come from the old concrete but the new. And the concrete will crack. If you can live with the cracking, I would pressure wash real good. drill and epoxy some rebar tips in old slab and pour on top. Use fiber not wire mesh. The fiber will control the cracking from getting bigger. and pour low slump. I would super plastize it.
thanks brownbagg for your comments... I'll have them scar the existing surface as well for better attachment of the new concrete.
Your method would not have any bonding agent?
as a concrete inspector for the last twenty two years. I have no evidence that concrete bonding agent actually work. I rather epoxy rebar in existing slab. If the bottom slab is clean from dirt and grease the new concrete will bond itself. no dirt, grease, grime, paint, oil etc.
Edited 2/3/2005 9:26 pm ET by BROWNBAGG
Will this carport be closed in then? Leveling the floor and changing the floor covering implies so. I don't know what area you are in, but here is a thought that might help this project -pin the edges of the slab like BB suggests and use some XPS foam in the interior areas. There the slab tickness will be reduced, but the floor ends up a bit more comfortable thermally.Do stick around. We have several archies heere. The ones with good ideaas and who don't have the "I Am the Lord" attitude are wonderfull people
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
thanks piffin and bb.... I'll keep your suggestions in mind. I"m letting the owners look over the drawings this Mardi Gras weekend. We had discussed using two layers of felt or modified bitumen too. I'll see which way the owner wants to go too...b/c money may be a factor here.
Yes, it is being enclosed for two bedrooms and a bath.
Thanks piffin... trust me, this girl is no LORD ;) , my dad raised me right and humble.
Thanks both of you for your help. :)
cler
oh, I'm in Louisiana... water is always a factor here :)
Edited 2/3/2005 10:10 pm ET by Design
we have an office in Baton rouge
Really, wow what a really small world BB. I work in Baton Rouge.
Cler