1
NCCER Concrete Construction |Review
Question and Answers| Fully Updated
Paper 2025
A slab is being poured on a super hot day, and the surface is drying way too fast. What’s a good
reason that’s a problem?
If the surface dries faster than the rest of the slab, it can lead to cracking because the concrete
shrinks unevenly. That messes with its strength and looks bad too.
A worker installs a 90° elbow but forgets to clean the pipe ends. What issue could that cause later
on?
Not cleaning the pipe means debris or oil could mess with the glue or seal, and that could
lead to leaks or the fitting coming loose later.
You’re laying out formwork but you notice it's not completely square. What risk are you taking
by continuing the pour anyway?
If the form isn't square, the concrete won't set with the right dimensions. That means parts
might not line up later in the build—costs more time and money to fix.
Someone uses high-slump concrete for a footing that needs to hold serious weight. Why’s that a
bad call?
High-slump means the mix is too wet. That weakens the concrete and makes it more likely to
fail under heavy loads—footings need strong, solid concrete.
, 2
While checking rebar placement, you see it’s too close to the edge of the form. What could that
cause once the concrete sets?
Rebar needs a cover of concrete to protect it. If it’s too close to the edge, moisture can reach
it and cause rust, which leads to cracks or failure over time.
The schedule says to strip formwork 12 hours after the pour. What’s something important you’d
want to double-check before doing that?
You’d want to check if the concrete has gained enough strength. Stripping too early can
cause it to collapse or get damaged—especially at the edges or corners.
A coworker is about to use PVC cement with a CPVC fitting. Why should you stop them?
The glue types are different. PVC cement won’t bond right with CPVC, and that could cause
the joint to leak or break apart later on.
On a construction site, why would someone choose precast concrete over cast-in-place?
Precast is made in a factory, so it’s usually better quality and faster to install. It also cuts
down weather delays since it’s already cured before it gets to the site.
Someone suggests using duct tape to seal threaded pipe joints temporarily. Is that actually
useful?
Not really—duct tape isn’t made for pressure systems. You’re better off using thread sealant
or Teflon tape to prevent leaks the right way.
, 3
You’re checking a foundation pour and notice segregation in the concrete. What’s the likely
cause?
That usually happens if the concrete was dropped from too high or moved around too much.
The heavy stuff sinks and the water floats up—makes the mix uneven.
A contractor wants to speed up a pour by skipping the vibrator. Why might that decision
backfire?
Without vibrating the concrete, you can get air pockets or honeycombing. That weakens the
structure and can lead to cracks or poor bonding.
The drawings call for a slope on a concrete sidewalk. What could happen if that slope is missed
during finishing?
If there’s no slope, water might pool up instead of draining. That leads to puddles, ice in cold
weather, and long-term surface damage.
You’re installing CPVC pipe in a hot area next to a boiler. What fitting consideration should be
made?
CPVC can handle hot water, but you need to make sure the fittings are rated for high temps
too—otherwise they might warp or fail.
While working with a laser level on a concrete slab, it keeps showing uneven spots. What could
be going wrong?
NCCER Concrete Construction |Review
Question and Answers| Fully Updated
Paper 2025
A slab is being poured on a super hot day, and the surface is drying way too fast. What’s a good
reason that’s a problem?
If the surface dries faster than the rest of the slab, it can lead to cracking because the concrete
shrinks unevenly. That messes with its strength and looks bad too.
A worker installs a 90° elbow but forgets to clean the pipe ends. What issue could that cause later
on?
Not cleaning the pipe means debris or oil could mess with the glue or seal, and that could
lead to leaks or the fitting coming loose later.
You’re laying out formwork but you notice it's not completely square. What risk are you taking
by continuing the pour anyway?
If the form isn't square, the concrete won't set with the right dimensions. That means parts
might not line up later in the build—costs more time and money to fix.
Someone uses high-slump concrete for a footing that needs to hold serious weight. Why’s that a
bad call?
High-slump means the mix is too wet. That weakens the concrete and makes it more likely to
fail under heavy loads—footings need strong, solid concrete.
, 2
While checking rebar placement, you see it’s too close to the edge of the form. What could that
cause once the concrete sets?
Rebar needs a cover of concrete to protect it. If it’s too close to the edge, moisture can reach
it and cause rust, which leads to cracks or failure over time.
The schedule says to strip formwork 12 hours after the pour. What’s something important you’d
want to double-check before doing that?
You’d want to check if the concrete has gained enough strength. Stripping too early can
cause it to collapse or get damaged—especially at the edges or corners.
A coworker is about to use PVC cement with a CPVC fitting. Why should you stop them?
The glue types are different. PVC cement won’t bond right with CPVC, and that could cause
the joint to leak or break apart later on.
On a construction site, why would someone choose precast concrete over cast-in-place?
Precast is made in a factory, so it’s usually better quality and faster to install. It also cuts
down weather delays since it’s already cured before it gets to the site.
Someone suggests using duct tape to seal threaded pipe joints temporarily. Is that actually
useful?
Not really—duct tape isn’t made for pressure systems. You’re better off using thread sealant
or Teflon tape to prevent leaks the right way.
, 3
You’re checking a foundation pour and notice segregation in the concrete. What’s the likely
cause?
That usually happens if the concrete was dropped from too high or moved around too much.
The heavy stuff sinks and the water floats up—makes the mix uneven.
A contractor wants to speed up a pour by skipping the vibrator. Why might that decision
backfire?
Without vibrating the concrete, you can get air pockets or honeycombing. That weakens the
structure and can lead to cracks or poor bonding.
The drawings call for a slope on a concrete sidewalk. What could happen if that slope is missed
during finishing?
If there’s no slope, water might pool up instead of draining. That leads to puddles, ice in cold
weather, and long-term surface damage.
You’re installing CPVC pipe in a hot area next to a boiler. What fitting consideration should be
made?
CPVC can handle hot water, but you need to make sure the fittings are rated for high temps
too—otherwise they might warp or fail.
While working with a laser level on a concrete slab, it keeps showing uneven spots. What could
be going wrong?
