Drywall (Sheetrock) and Paint Basics
Drywall is gypsum board. We want it
to look nice, give us some fire protection, reduce air flow, etc.
Sheetrock,
itself, can expand and contract fairly nicely. When it’s cracking it’s because
the substrate supporting it is moving. We know that all building materials
move, so our goal is to build in expansion joints to allow the substrates to
move.
Property
installed and taped drywall makes a good air barrier. When you add your paint
you have a nice vapor retarder. This is why architects like the versatility of
drywall. Also, you’ll notice fire code drywall being used as draftstops, smoke
walls, and firewalls.
Treated
gypsum board is frequently specified to be used in wet areas. If the budget
will allow it, substitute their “green board” for cement board. Cement board
will last longer.
Although
not specified all over, we like to use 5/8” fire code drywall all over. The
5/8” F.C. is not extremely more expensive and when applied properly over each side
of a wall you’ll get a one hour fire rated system all over.
Stain
breaks down in ultraviolet light more quickly than paints. This is why you have
to “re-stain” so often. Quite often “solid body” stain is really a thin paint,
so its value is limited.
Primers
are used to provide a surface to keep the finished paint from over absorbing
and provide a more adhesive surface for the paint. Primers also attempt to
reduce the effect of tannic acid and salts from wood. Normally, oil based
primers hold back tannic acid in wood. Latex primers seem to work okay on
masonry, drywall and concrete. Generally, redwood and cedar should be primed
with an oil base primer.
Foundation Basics: Water Management
When it comes to controlling water at the foundation level, your goals are:
1. Keep
the groundwater out
2. Support
the building above
3. Support
your HVAC design
Water moves
through foundations many ways, via water vapor, hydrostatic pressure, etc. Your
first priority is to design systems to keep the water moving away from your
foundation in the first place, the management of water. No structural system by
itself is water tight.
If utilizing a
basement:
a. Perforated
drain tile surrounded by coarse gravel
b. Coarse
gravel under the slab and polyethylene type vapor barrier
c. Damproofing
on the exterior side
d. Roof
precipitation flowing away from the foundation wall
If utilizing a
“slab on grade design”:
a. Roof
water is directed away from the foundation
b. Vapor
barrier on the bottom of the slab
c. Drainage
gravel under the slab
Coating an
exterior foundation with bituminous materials creating damproofing. Damproofing
resists the capillary forces of water, but not the hydrostatic forces.
“Waterproofing” resists the hydrostatic pressure forces of water. Keep water
flowing away from your building and foundation and therefore create no a
hydrostatic environment.
Fire Preparedness
This article reminds me of when I was in school. It's an interesting perspective on a big picture issue.
-Mark
-Mark
'Critter' Management
Keeping your
building resistant to dust and critters is one of your highest priorities:
1. Seal
up your exteriors and inspect them annually. Check your walls, roofs, and
foundations for holes and penetrations.
2. Seal
up your interior baseboards to keep critters from moving around should they get
into your building.
3. Your
building should make it difficult for critters to find food and water. Keep
water out, keep your plumbing and ductwork from leaking. Keep the food in
sealed containers. Keep your waste in sealed containers. Keep wood and paper
from getting wet.
These steps can
reduce your expenses associated with pesticides and critter removal vendors.
If budgets would
allow, use HVAC filters with MERV ratings of 6 to 8. ASHRE 35% or better.
Innovations in HVAC
This is one of the many innovative ideas being employed in the renovation work with tight working conditions.
-Mark
-Mark
Preconstruction Budget Risks for Local Government Projects (3 of 3)
Part Three: Human Error and the Unknown
On any local government construction project, human beings
design and build every aspect and every human is fallible. Anyone who says they can build a perfect job
on a school or jail or courthouse is lying.
After decades in the business, Shireman Construction has
built up a list of “lessons learned” that we use as a checklist to eliminate
errors. We catch numerous design errors and poor choices and save
the owner money on every job we work as a construction manager.
In fact, most of the cost savings are wrung out of the job
in the design stages –see the graph above. That’s why it’s critical to get a CM
on board as early as possible to team closely with the Architect and bring a
fresh set of eyes to a project.
But try as we might, there is no way to eliminate all
unforeseen costs on a construction projects. The “unknown” is a big risk, and on new construction you might uncover rock, sinkholes, or
old buried fuel tanks that the geotechnical report couldn’t catch.
On renovations you might uncover previously unknown
asbestos, pests, structural problems, lead paint, poor foundations, etc. that
were undiscovered despite thorough investigations by the design team.
Then there’s human error. The architects and engineers make tens of thousands of
decisions and product choices, and all of them won’t be perfect. A team of low-bid contractors will go out and dig a hole in
the ground and build a multi-million dollar facility from scratch.
So knowing that we’re all human and some mistakes and
unforeseen challenges will emerge, Shireman uses a unique “built-in contingency”
system to plan ahead.
Within each low bid contract will be contingency funds to be
used when unforeseen difficulties emerge, with the approval of Shireman, the
architect and owner.
What make this so great? Because we have planned ahead
together, and the funds can be expended and issues promptly fixed in the field.
For government officials, this also means that instead of
going over numerous “change orders” and annoying the general public in open
meetings, these issues can be planned for and adjusted immediately in the
field. Imagine monthly public meetings where instead of approving
every tweak and minor change order request while the project is held up, you
can truthfully report to the satisfied taxpaying public that the project
remains under budget.
By planning ahead for the unknown and human errors on local
government construction the project budget will be saved and the public will be
happy.
Thanks for reading our
three-part series on preconstruction budget risks.
Let us help you avoid
budget pitfalls.
For more tips and tricks on local government construction and
real life examples – s
