Rules of Thumb for Demo work?? - Contractor Talk - Professional Construction and Remodeling Forum

SiteGirl · 06-02-2008, 12:10 PM

What are some rules of thumb for demo work??

**joasis** · 06-02-2008, 12:17 PM

Make a profit?

So what are you asking exactly?

I just went through a demo bid and have yet to see any 2 that are even close...the amount of material to remove, number of roll offs, construction of the building, concrete, depth of footings and foundations, utilities, returning site to grade.....on and on.

SiteGirl · 06-02-2008, 12:29 PM

Im trying to bid a demo job, for the first time and Im running into, where do I start? Its about 3850 s.f. 1 story retail space. There's carpet, wallpaper, doors and (4) storefronts to be removed. I know your supposed to figure how many men, how many days, but cant figure it out...

**joasis** · 06-02-2008, 04:17 PM

You will catch some grief on this topic, but I will start off by pointing out that no one can accurately tell you how to estimate this....estimating is a difficult trade to just jump into, since most estimators have been in the field long before they jump into the numbers side.

I know a guy that used to clear retail properties, which is not as much demo as you would think...he basically gave a bid to empty the area, and salvaged the fixtures for his profit.

You can try it on the "safe side" by seeing if your customer will agree to a cost plus basis......hire your labor from a temp agency so you are covered on WC and insurance, and then be on site to run the show. At the end, you add up the costs, add 10% (or whatever you agree to) and bill the customer. Take the percentage as being paid to see what it costs, and then next time, you will know how many man hours are involved in gutting a retail space. Good luck.

BTW, in the contracting business, demolition generally refers to tearing down of existing structures, not what you are doing.

**genecarp** · 06-02-2008, 06:02 PM

dont hit the gas main.

rbsremodeling · 06-02-2008, 06:05 PM

always make sure the electrical breakers are off

**genecarp** · 06-02-2008, 06:20 PM

Locate The Water Main, Prior To Starting.

rbsremodeling · 06-02-2008, 06:26 PM

by the time someone says what's that noise?? its to late

sapotech101 · 06-02-2008, 06:42 PM

make sure you squechule the dumpsters on the right times of the day or your going to have to do double the work, early day, garbage every ware or the opposite a half full dumpster because he came to early and he as to go knowing how to pack is also a most if your paying flat fee for the dumpster dont just trow stuff in there. Insulation first then drywall to compress, any lumber make sure is aling or youll lose alot of space in the box, furniture brake. Dumpsters are a big part of demo and motivated guys, if your getting guys from an agency i ussually give them a task for the day and tell them if they finish early i give them full day pay that ussually makes them want to work harder. good luck hope every thing works out

firemike · 06-02-2008, 09:58 PM

Quote:

What are some rules of thumb for demo work??

Don't start at the bottom of a structure and try to work your way up....

SiteGirl · 06-03-2008, 10:42 AM

Thanks!!

K2 · 06-03-2008, 11:04 AM

You should know a little about hazardous materials and what you might run into and what might be enforced. They are pretty easy around here but I would not count on it. I saw 7 state troopers unloading a truck at the dump years ago. Maybe looking for a body or maybe some illegal material... Bigger demo's might require a permit.

Dmax Consulting · 09-11-2008, 07:39 PM

Great post!

I am in a similar situation and am also looking for advice.

sk071077 · 03-03-2009, 06:22 PM

Wear a mask, and gloves, watch out for nails and other sharp objects, be aware of things like bearing walls, plumbing and electrical, plan out what your going to do before you do it. Don't hurt your self.

knucklehead · 03-03-2009, 06:45 PM

Just guess. thats what bidding is,right?

Snobnd · 03-04-2009, 09:44 PM

Quote:

Originally Posted by knucklehead

Just guess. thats what bidding is,right?

Tools tools tools- and Lots of insurance! ....Oh ya and a box of band-aid

JDavis21835 · 03-04-2009, 09:51 PM

I know its an old thread, but I wanted to cover a little something.

Quote:

Originally Posted by firemike

Don't start at the bottom of a structure and try to work your way up....

This may be a common sense approach, but there are ways you can start at the bottom and work your way up. Heres one I worked on in Oregon. The reactor dome was over 250ft tall when we started. Did it all from the bottom.

firemike · 03-05-2009, 03:25 PM

There is always an exception to every rule! :-) I am guessing the structure was strong enough to remain intact and self supporting as you "whittled" it down.

greg24k · 03-05-2009, 07:14 PM

Quote:

Originally Posted by JDavis21835

I know its an old thread, but I wanted to cover a little something.

This may be a common sense approach, but there are ways you can start at the bottom and work your way up. Heres one I worked on in Oregon. The reactor dome was over 250ft tall when we started. Did it all from the bottom.

What about a little dynamite

to soften the whole thing up and make a nice pile which is easy to scoop... that would be best the solution a case like this, unless there is some sorts of restrictions.

JDavis21835 · 03-05-2009, 07:43 PM

Well, the concrete was 3 feet thick. The interior of the building had 1/2-inch thick steel plate with 4in tall x 2in wide I beams welded to it. The beams were imbedded into the concrete wall. We would hammer out 10 feet tall sections at a time. Basically like we were making a giant core bit. We would hammer out three triangles, then at the point contacting the ground, we would hammer away at that section. With the weight of the structure above, it would slowly crumble, with help from the hammers of course. The steel inside also helped keeping the process slow and predictable.

As for dynamite. This plant had the first cooling tower to be imploded. It was up hill and far enough away to be done this way. The reactor building you see here was to close to the spent fuel casks to be imploded. They were afraid of a few issues. 1 The storage casks were literally in the shadow of the building. 2 They were afraid that the dust created would cause damage to the cooling system for those casks. 3 You see the bolt looks piece on the side of the structure. They are actually caps for a cable system. The thinking behind the cables were if for some reason there was a catastrophic failure of the reactor and an explosion happened, the cables would keep the structure mostly in tact. So those would be an issue for explosives. Top that off, the cables were coated in a grease that is supposedly a known carcinogen. We had to pull a pig behind the cable as we pulled it out of the structure. As much grease as possible had to be disposed off to a proper landfill.