Doublewide demo

[Keith Merrell]

Hi guys,

I am quoting a demo for a 1600SF double wide. It has a couple awnings, so total under roof would be approx. 1900SF. I did a demo for a very old house last December that was 1400SF. I used 40 yd roll offs on the last one and I ended up with about 4 1/2 of them and they ended up at scaling out to 10 tons each about. I am thinking to figure on 6 roll offs at least. I am going to quote this as labor plus the actual cost for permit and debris disposal. Also, to get a permit here they don't require asbestos testing. Is that a good idea to cover yourself? Also what are some good alternatives to 40 yd roll off cans? High side dump trailers are non existent in this small town. The difficulty I had on the last demo was how long it took to get the cans picked up and the inefficiency because of that. Other question is how do you deal with the mobile home frame / axles? Cut up with fire man saw and scrap? Also, no garbage inside. Thanks.

 

[Keith Merrell]

 

[gwhammy]

I just did a single wide that had rooms added down one side so basically a double wide. It took two 40 yd. dumpsters and they were full. I beat the material in layers with my 18,000 excavator to get the most from them. Sorted the frame and any metal I could out to keep the weight down. Usually a day minimum is what I charge. I think total dumpster fee was 1300 for that job. The frame mashed up enough to load it and the axles on my gooseneck to haul to the salvage yard along with water heater and other metal. It usually takes a hour or so to load a dumpster, less if I use the 40,000 lb. excavator.

 

[Old Doug]

There is alot of steel and aluminum there if you have time.

 

[CM1995]

KM I think you are on track as far as the estimate goes. Over time you'll be able to dial it down to the CY/TN of debris. Demo is just as much an art as a science IMO.

Here's my rule of thumb for estimating wood frame residential structures including house trailers and modular -

1,000 SF = 100 CY - This only works if there is no personal contents in the home.
1 - 30 CY can will average 9 tons over the project.

The first cans will be lighter and the last cans will be heavier due to the fines. Also the above does not take into account concrete - footings, slab, etc. or brick/block. Those materials are not classified as waste so here they can go to an inert fill dump. We haul that type debris in dump trucks. Typical dump fee here for that type of mixed material is $50-100 per load. The crushing yards accept clean concrete for free.

I also have a factor built into my demo spreadsheet if there is something out of the normal with the structure like a lot of architectural elements, steep roofs, personal contents or if the house has been burned. The factor ranges from .2 to .5 depending on existing conditions and it just increases the demo debris volume 20-50%. Burnt houses usually have personal content in them and create the heaviest cans in my experience.

For house trailers, like Doug said have a fair amount of metal in them. An excavator with a thumb can peal the siding off, pick through the internal metal and fold the frame up. We always have a 30 or 40 yard can for metal only. With a decent 30K lb + excavator you can fold a trailer frame up so it fits in a 30/40 yard can. I've done it with our 953C loader.

Same here on the demos we do. High sided trailer dumps are here but hard to get and roll-off service takes forever to pull the cans. If we did more demo I would consider buying a 60-70 CY dump trailer.a

KM what type of machine will you be using?

 

[Keith Merrell]

CM thanks for the response. I plan to use a 6 ton mini with a thumb, definitely undersized but I own it. I have no problem loading 40 yd cans with it. Last house I did it was down in a couple hours and it took me 30-45 min to load a can. But the problem like you said is how long they take to pull them. And yes with all of that metal my thinking was pull it off and start making a scrap pile at my yard or just taking it straight to the recyclers. What would your preferred size machine be for this job? Komatsu 160?

 

[CM1995]

Well my preferred size machine would be what we own which would either be a 321DL or 325FL. 55K lb machine.

If I did have to pick the perfect size machine for residential and light commercial demo it would be a 315 (35K lb) compact radius or the equivalent in other brands. That size machine is small enough to fit on a heavy tag trailer but big enough to handle that type of demo.

Your 6 tonner is more than capable for this type work it'll just take a little longer and since you own it, run it. Probably want to have a demo saw on hand with one of those nice diamond metal cutting blades on it to either cut the frame or at least score it where you can either fold it or break it with you 12T.

A smaller ex with a thumb is better at sorting metal IMO.

 

[materthegreater]

A rotating grapple speeds things up a bit

 

[gwhammy]

I've used a 12,000 lb. with thumb on houses before. They actually work fairly good. The 40,000 lb. excavator with hydraulic thumb I'm using now worked great on the two story house I just took down. It took 8 40 yd cans and total cost to the dumpster company was around 6800. Landfills in this farming community are 50 to 75 miles and they charge around 280 a load to haul off and bring empty. They will pickup and bring a empty every night. I'm usually working several jobs real close and only live a couple miles from town so loading every morning before I go elsewhere is not a problem.

Cm is right on the tons per container. The first ones were around 7 to 9 tons with the last one having to be off loaded into two containers. I got 21 ton on it and the truck couldn't load. I try to be real careful with anything that doesn't have to go to a landfill. 60 a ton means 3 cents a lb. so any bricks concrete or steel adds up fast.

 

[Old Doug]

But the problem like you said is how long they take to pull them. And yes with all of that metal my thinking was pull it off and start making a scrap pile at my yard or just taking it straight to the recyclers. What would your preferred size machine be for this job? Komatsu 160?

Dont let the scrap hit the ground until your at the scrap yard every time you handle it its costing you money.

 

[KSSS]

I have torn down numerous single and double wides with a 6 ton mini ex. Sometimes its the only thing that really fits. The mini will pull apart the steel cross members between the steel beams. We sometimes we demo saw the beams, sometimes you can twist them in two with the mini, but there is certainly enough steel to make it worth a trip to the recycler.

 

[cadre2040]

KM I think you are on track as far as the estimate goes. Over time you'll be able to dial it down to the CY/TN of debris. Demo is just as much an art as a science IMO.

Here's my rule of thumb for estimating wood frame residential structures including house trailers and modular -

1,000 SF = 100 CY - This only works if there is no personal contents in the home.
1 - 30 CY can will average 9 tons over the project.

The first cans will be lighter and the last cans will be heavier due to the fines. Also the above does not take into account concrete - footings, slab, etc. or brick/block. Those materials are not classified as waste so here they can go to an inert fill dump. We haul that type debris in dump trucks. Typical dump fee here for that type of mixed material is $50-100 per load. The crushing yards accept clean concrete for free.

I also have a factor built into my demo spreadsheet if there is something out of the normal with the structure like a lot of architectural elements, steep roofs, personal contents or if the house has been burned. The factor ranges from .2 to .5 depending on existing conditions and it just increases the demo debris volume 20-50%. Burnt houses usually have personal content in them and create the heaviest cans in my experience.

For house trailers, like Doug said have a fair amount of metal in them. An excavator with a thumb can peal the siding off, pick through the internal metal and fold the frame up. We always have a 30 or 40 yard can for metal only. With a decent 30K lb + excavator you can fold a trailer frame up so it fits in a 30/40 yard can. I've done it with our 953C loader.

Same here on the demos we do. High sided trailer dumps are here but hard to get and roll-off service takes forever to pull the cans. If we did more demo I would consider buying a 60-70 CY dump trailer.a

KM what type of machine will you be using?

That's very insightful I miss bids more often than not.
I think I'm way over calculating how much debris there actually would be.
Example (photos In reply) had a two houses one already collapsed demo bid. 3780 total sq footage. I calculated about 640 cy or 180 tons.. which made everything crazy expensive.. I'm pretty accurate on mobile home by suck at normal house quotes

 

[CM1995]

That's very insightful I miss bids more often than not.

Couple of things to consider -

"I've never lost money on a job I didn't get".
"If you are constantly getting beat on bids you are pricing too high"
"If you are getting everything you bid then you are not pricing high enough"

Quality estimates just take time and experience to develop.

 

[cadre2040]

Couple of things to consider -

"I've never lost money on a job I didn't get".
"If you are constantly getting beat on bids you are pricing too high"
"If you are getting everything you bid then you are not pricing high enough"

Quality estimates just take time and experience to develop.

Good advice, I have thought about just taking a hit on the first couple just to get a better feel and idea on weights and cy. I was all was trying to go 94lbs per sqft I'm going use this formula and go from there.
Thanks for the help CM1995

 

[gwhammy]

See if you can talk someone into doing one by the hour. We used a formula off the internet for the last two story and came up around 4000 dollars less than what it showed to use as lbs. per square foot. I charge a minumum of 150 dollars a dumpster to load them after I have the house down. In this small town I can only get one dumpster per day. Usually leave an extra machine on site and go every morning and load on my way to another job. Town is only a couple miles and most of my work is around that area. Our 40 yd dumpsters are 62 dollars a ton and 280 a haul plus 4.50 a day plus a delivery fee on the first emty. All the land fills are 50 to 75 miles away so a dump truck won't work.

 

[cadre2040]

See if you can talk someone into doing one by the hour. We used a formula off the internet for the last two story and came up around 4000 dollars less than what it showed to use as lbs. per square foot. I charge a minumum of 150 dollars a dumpster to load them after I have the house down. In this small town I can only get one dumpster per day. Usually leave an extra machine on site and go every morning and load on my way to another job. Town is only a couple miles and most of my work is around that area. Our 40 yd dumpsters are 62 dollars a ton and 280 a haul plus 4.50 a day plus a delivery fee on the first emty. All the land fills are 50 to 75 miles away so a dump truck won't work.

I understand the dumpster pain. The last job it took them 10 days to swap out 4 dumpsters. Killed me with the excavator rental

 

[CM1995]

I understand the dumpster pain. The last job it took them 10 days to swap out 4 dumpsters. Killed me with the excavator rental

Same here the PITA is always getting boxes swapped. In order to make any real money doing demo you have to own your own equipment and have at least one roll off truck with several cans or a high volume dump trailer. It's the only way to control the time it takes which time dictates profitability.

We pretty much only do demo if it is ancillary to the overall site project. Like the private school dining hall we are finishing up. The project involved tearing the old one down but the site work and utilities were a larger dollar volume of the contract than just the demo.

C2040 don't take it in the shorts on one just to learn. Like GW said maybe you can get an owner to do a demo by the hour and then per the can to the landfill. If you can't find an owner willing to do that then you might offer to price the equipment side and then the disposal per can/haul/ton. That way you could get a handle on the volume side of it.

 

[KSSS]

 

[KSSS]

Sorry about that. CM1995 obviously feel free to clean that up. Good thing dial up is gone.

 

[cadre2040]

Same here the PITA is always getting boxes swapped. In order to make any real money doing demo you have to own your own equipment and have at least one roll off truck with several cans or a high volume dump trailer. It's the only way to control the time it takes which time dictates profitability.

We pretty much only do demo if it is ancillary to the overall site project. Like the private school dining hall we are finishing up. The project involved tearing the old one down but the site work and utilities were a larger dollar volume of the contract than just the demo.

C2040 don't take it in the shorts on one just to learn. Like GW said maybe you can get an owner to do a demo by the hour and then per the can to the landfill. If you can't find an owner willing to do that then you might offer to price the equipment side and then the disposal per can/haul/ton. That way you could get a handle on the volume side of it.

I couldn't agree more cm1995. Owning your equipment is a must. Even the rental equipment is getting thin rn especially s excavator with a thumb around here an over priced used machine is about all that is available working on a cat 317 or Volvo 160 at the moment we'll see how that goes and how long it will take to get it