I am a concrete contractor in Houston, TX. (www.conspecinc.com) After reading these treads I am amazed at how little people really know about concrete placement. First, the smaller the job = the more it costs because we are charged a "short load fee" for orders under 6 yards. This fee can be up to $175 "plus" the cost of the concrete. Also - for slab on grade applications wire mesh is much better than rebar (contrary to popular opinion). It has to do with the fact that reinforcement on "slab on grade" applications is based upon the strength of the GRADE not necessarily the reinforcement. The reinforcement just prevents the crack from developing and wire mesh does a better job. I address this on my website. Finally, concrete costs have gone up as the economy (gas prices), drive costs. I charge $6 to $7 PSF for stamped colored concrete and $3.50 to $4 for standard. In Houston, contractors have a habit of putting wood for control joints which ultimately rots out. Not a good idea. I don't use wood for control joints unless requested. Also concrete can be ordered in MANY WAYS! A contractor can order substandard concrete (but the owner does not know the difference), cheap.... but GOOD concrete costs about $80 per yard. In short a concrete patio "should" cost $3.50 to $4 PSF in Houston that is - if you seek quality. Concrete can have "fillers" which after 28 days "will" give you 3000 PSI but "after" this period it will slowly diminish. Good concrete however, increases its strength with age. Good concrete takes 50 years to totally cure. My website gives you the truth about concrete placement.

Well, The engineer did provide an updated design and stamp of approval on the poured product. The builder moved quick to remedy the situation. I'm still a bit concerned though, as I contacted several structural engineers and 2 of them said they would NEVER add-on as described and the other 2 said it was perfectly acceptable. I'm waiting to hear back from the PTI (Post-Tensioning Institute) to see what they say. I don't know that I have any recourse except to walk away from my deposit which is not an insignificant amount of money. Any yes, the soil conditions and cost both contribute to the use of the post-tensioned slab which is the most common construction method here in Houston.

Not a tile pro, just an interested amature that's never done any outdoor tile setting, but I don't *think* you need to do anything but clean the surface well. Cement board is used to provide a surface for the thinset to adhere to, but it should stick to the cement just fine. UNLESS its been sealed or painted, then you may need to mechanically remove some of the surface. Ditra is wonderful: it replaces the thinset in horizontal applications, and helps keep cracks in your slab from becoming cracks in the tile. But if the slab is stable and crackfree, I don't think it would do anything but add about $1.50/ft to your materials cost. You DO need to use a tile approved for outdoor use-- tiles that aren't won't survive the thaw/freeze cycle. Personally, wouldn't add the heat system at this time unless you have a pretty clear intention of finishing the space later. I'm not sure an electric system can be used outdoors, and a hydronic system for a single room is rarely done due to the complexity and cost of other equipment, like the boiler, etc. If the rest of your home already has radiant hydronic and the slab is in a spot where it would be simple to tie the deck system into the whole house, it would probably be worthwhile. Personally, I'd save the money now, spend it later on a new floor if needed. BUT I know of people at Big Sky and other ski areas that have hydronic radiant heat under their decks, sidewalks and driveways. They melt the snow as it falls rather than paying someone to shovel it [they are in the income bracket that doesn't shovel its own walks]. Seems pretty environmentally irresponsible to me...

Here are a couple photos from when the condo was still under construction. The yard, more or less, looks the same though: (This one is a view from the outside of the front patio yard and walls) (This it the view looking outwards from the perspective of the yard and as if you have just come out from the front door... there's a concrete slab not far from the AC next to the sliding glass door now that isn't in this picture) This is in Lakewood, CA 90712 I believe is the zipcode. The pipe with the red top sticking out is where the drainage is. Currently they installed one of those green drainage basket things that sticks above ground. The ground around it seems graded to drain towards it too. The dirt that's there right now looks about the same as in the picture - is that road base?