any concrete guys on here? have a question

[txtrophy85]

Scenario:

we are building a flagstone patio in our backyard, first a slab poured and then flagstone to be layed over it.

we were pouring concrete today and ran into a very unforeseen delay and the end result being we only got about 80 sq.ft of concrete poured out of a 500 sq. slab. Slab has wire mesh , rebar around the footing and along the home as well as being doweled into the slab with the exception of the existing slab (9x10 surface pad which I chose not to dowel into because of its 3-4" thickness, was afraid of cracking or other issues, this is where the 80 sq. section was poured)

anyway, due to the delay we are now going to have a cold joint....there was no joint placed where it ends, just kind of tapers off.


do anyone with more experience than me foresee an issue with this? I was planning on having them throw in some more mesh and dowel into where it end to the new pour and then finish it off.


thanks for the response

[El General]

You doweled your patio into your house slab? That is a bad idea.

Why don't you just jackhammer the 80 SF out of you are worried about it? It shouldn't be more than a yard of concrete.

[txtrophy85]

You doweld your patio into your house slab? That is a bad idea.

Why don't you just jackhammer the 80 SF out of you are worried about it? It shouldn't be more than a yard of concrete.

why is doweling it into the slab a bad idea?

[El General]

why is doweling it into the slab a bad idea?

Never connect flatwork to structural. If your patio heaves, now it can crack your house slab.

[MASTERS]

Never connect flatwork to structural. If your patio heaves, now it can crack your house slab.

This, I've seen it happen more than once....

[El General]

Standard practice is to use black asphalt expansion joint as an isolation joint between flatwork and structural.

[txtrophy85]

Never connect flatwork to structural. If your patio heaves, now it can crack your house slab.

hmmm...most of the patios ive seen done we tied to the house slab.


for what its worth we are in the hill country on limestone with very little movement....we have not doweled it in yet....should we take them out?

[El General]

hmmm...most of the patios ive seen done we tied to the house slab.


for what its worth we are in the hill country on limestone with very little movement....we have not doweled it in yet....should we take them out?

Yes, a lot of people do that, but a lot of people don't know what they are doing. Yes, I would take the dowels out.

[125Dad]

I agree take out the dowels

[El General]

BTW, I have been pouring concrete for 25 years since I was 13 years old. I have done everything from patios and driveways to high rise structural and everything in between.

[txtrophy85]

what would cause the patio to heave?

[El General]

what would cause the patio to heave?

A whole bunch of different things. The bottom line is that it isn't worth it.

[BertramBass]

I have noticed in San Antonio, Austin and on into Hill country that they dowel in there flatwork. Structural engineers require rebar to extend out the garage beam to tie in the driveway. Cedar 1x4 is used instead of a black asphalt strip at the expansion joint. Cedar shrinks, breaks and comes apart and building supply houses sell a plastic filler strip it slide into its place.

[BertramBass]

what would cause the patio to heave?

Usually the the patio is on expansive soil and when moisture gets under there it will heave.

[mavrick]

Have them chip away anything that is loose. Paint the area with the white binding glue and finish your pour. It should be fine the stone will cover the joint so it should work out fine.