i have seen it done by the pros. they mount a rail system onto to wall with conc anchors. then they run a wet saw up. they go fast. not so sure a cinderblock wall will have rebar will it? it gets messy with all the slurry. i would farm out this work.

CMU walls quite often have reinforcing. Unreinforced masonry is fairly uncommon nowadays. It's actually forbidden by code in CA.

This is what they do to cut "Concrete" walls. We're talking about a block wall here.

For a door opening, just cut the rebar, no sweat. The rebar is more for temperature swings involving expansion/contraction than strength, fyi.

Cheers,

And for seismic considerations. ;)

If he's certain it's just a "block" wall with no reinforcing then he should be okay but due diligence would require him still checking to make sure there's no structural function being performed by the wall first - that's all I'm sayin'.

The actual cutting part is probably the easy part!

I have seen guys ''cut'' block with a hammer. Block is soft, and even if the cells have been filled, it is not anywhere near as tough as concrete.

Concrete dust is VERY bad for your lungs !!!! A wet saw, or a mist sprayed fron a hose is essential. Even a respirator cannot protect you 100% from that dust, but it is a lot better than no protection at all.

I would agree. A saw is likely not needed for block walls. Just makes a neater job for the half block removals?

Hammer away.

+1 on the dust mask too.

viagra?

The building was built in the early '70's and is in MA. The office space we occupy was added sometime later, but no later than the mid '80's. The main portion of the building is used for warehouse space. A previous owner added some rooms to the interior side of the warehouse and we want to add a door from the office hall into one of the rooms to gain additional office space. This door would pass through what was originally an exterior wall.

I checked the local yellow pages and there were a handful of listing under concrete cutting and coring and based on what I've read in this thread, I am most likely going to leave this to an expert.

What did the experts find out dean?

Not sure yet. Did inventory the end of last week and am heading out to a trade show this week. Won't be around to have someone take a better look and quote until next week at the earliest.