Frequently Asked Questions
Why do I need an asbestos inspection?
All commercial renovations or demolitions require a certified asbestos inspector
to take samples of the building materials and have them tested for the presence
of asbestos prior to renovation or demolition. The Minnesota Pollution Control
Agency also dictates that inspections must occur under other circumstances:
- A building owner who suspects his property may contain asbestos
must conduct an inspection.
- Buildings that are to be moved or dismantled and reassembled
at a new location must be inspected for asbestos.
- Buildings to be intentionally burned for fire training must
have an asbestos inspection performed.
Hengel is certified by
the MPCA to conduct these inspections. Contact our office for more
information or to schedule an inspection.
What is a cubic yard?
If you picture a box that is three feet tall, three feet deep and three
feet wide, that’s one cubic yard. All concrete, sand, aggregate and
topsoil products are measured by the cubic yard.
How do I figure out how many cubic yards or tons of product I need?
The calculator page is a good place
to start. When you have an irregularly shaped area, as most are, you simply
have to estimate the average length,
width and depth when imputing data into the calculator. If you want
some help or have a question, call us at (218) 746-3355.
Can we pick up materials ourselves?
Yes! No appointment or call ahead is necessary. Just show up with your
open bed truck or trailer during regular summer business hours (6 AM
to 6 PM Monday-Friday and 8 AM to 12 PM on Saturdays), and we will load you in
just a few minutes. Call our office at (218) 746-3355 for winter hours.
Directions to Hengel.
How much will my truck hold?
A standard half-ton pickup with a six foot bed will hold about two
cubic yards of lightweight material or one cubic yard of heavier material
(like topsoil) or one-half cubic yard of very heavy material (such as sand
or gravel).
What makes good quality concrete?
There are several basic requirements for good quality concrete:
- Good materials (cement, aggregate admixtures and water)
- Proper proportioning of these materials (see below)
- Thorough mixing
- Skillful placing and finishing
- Proper curing
Proportioning is simply deciding how much of each ingredient will be
put in the concrete. A temptation to use too much water generally results
from an effort to make placing operations easier for the contractor. Overly
wet concrete flows into the forms more readily and is easier to compact and
strike off. Everything about overly wet concrete is easier—except the
maintenance problems that will begin to appear on a surface that could just
as easily have been trouble-free for many years.
How is curing accomplished?
The newly placed concrete should be covered or sprayed with a material
that will retain the moisture within the mix. Membrane-curing compounds sprayed
on the surface are most commonly used. They must be applied immediately after
the concrete is given its final finish and care must be taken to apply them
thoroughly and uniformly.
What amount of time must concrete cure before being useable?
Proper curing greatly increases concrete strength and durability. Concrete
hardens as a result of hydration, which is the chemical reaction between
cement and water. However, hydration only occurs if little to no water is
lost during the early stages of this chemical reaction and if the concrete’s
temperature stays within a suitable range. The temperature of new concrete
should not be allowed to fall below 50 degrees during the curing period.
Concrete should not be put into service generally before 3 to 7 days after
placement. This is dependent on time of year, with winter being the slowest
curing season.
How can I make my concrete driveway less prone to damage from freezing
weather?
When ordering concrete for outdoor applications (driveways, patios,
etc.), always request air-entrained concrete. Entrained air is air
that is purposely incorporated into a concrete mix, primarily to make the
concrete
resistant to deterioration caused by freezing and thawing and the use
of de-icing salts. These air pockets relieve internal pressure on the concrete
by providing tiny chambers for water to expand into when it freezes
without
damaging the integrity of the structure. As the owner, you can also
help prevent damage by reducing or eliminating the use of de-icing agents
on exterior
slabs. These agents contain chemicals that result in an increased number
of freeze-thaw cycles. This process opens capillaries in the concrete
which impacts the intregrity of the slab and causes scaling. Sand is a
better alternate
for dealing with slippery surfaces.
What makes concrete crack?
Concrete "shrinks" slightly as it hardens. A normal shrinkage rate
is approximately 1/8" per 100 linear feet. This shrinkage is caused
by loss of excess water from the mix. The "wetter" the mix, the
higher the shrinkage rate. Control joints should be placed in the concrete
at intervals equal to 2.5 times (in feet) the thickness of the slab. For
example, a slab 4" thick should have control joints every 10 feet. Even
with the installation of control joints and proper proportioning, it is important
to remember that some cracking can still occur.
How do you find a good contractor?
When selecting a contractor, there’s more to consider than just cost.
Knowledge, competence, integrity and experience are additional qualities
to seek in a contractor. Take a look at a few of the contractors' completed
jobs, particularly some that were done several years ago. If you like what
you see, you can feel easier about seeking bids from them, knowing they do
good quality work.
What types of materials can I bring to Hengel’s landfill?
Hengel operates demolition landfills. This means that we are certified
by the state of MN to dispose of materials typically used in the building
process. While we can accept other types of waste, they must be transported
by our staff and disposed of at other sanitary landfills. Consequently
there is an additional charge associated with dropping these items at our
site. |
