Question 1

How do you keep grout cells clean while you're laying?

Accepted Answer

Mortar droppings in a cell that's getting grouted cause voids, and the inspector can fail the pour. It's one of the clearest signs of a mason who knows structural block. Say you keep the mortar bed off the cross webs of cells that get grouted Mention cutting the squeeze-out inside the cell as you go, not just on the face Talk about using cleanout units at the bottom of a lift and actually clearing them Give a moment when you caught droppings before the pour and fixed it

Question 2

Walk me through getting a wall ready for a grout pour.

Accepted Answer

The pour is where a structural wall passes or fails, and a lot can go wrong between the last course and the pump. Check that vertical bars are in the right cells, centered and lapped the length the drawings call for Confirm cleanouts are clear, then close them once the inspector has looked Know the lift height you're allowed to pour and why short lifts matter Consolidate each cell with a rod or vibrator, then reconsolidate if the spec calls for it

Question 3

What's a bond beam and how do you build one?

Accepted Answer

Bond beams tie a wall together horizontally. Getting them wrong can mean tearing out courses. Explain it's a course of bond beam or knockout units with horizontal bars running through it Say you place the bars at the height and size shown on the drawings and keep them off the bottom of the channel Mention grouting it solid, and how you keep grout from running down ungrouted cells below Note where bond beams usually sit, such as at floor lines, roof bearing and tops of walls

Question 4

Where do control joints go in a block wall, and why?

Accepted Answer

Concrete block shrinks as it cures. Without control joints the wall cracks where it wants to, and that ends up on the contractor's warranty list. Say you follow the drawings first, since the architect or engineer sets the spacing Mention typical spots: near openings, at changes in wall height and at intervals along long runs Describe the units or gasket used to keep lateral strength while letting the wall move Say horizontal reinforcing stops or is detailed at the joint the way the drawings show

Question 5

How do you handle laying block in cold weather?

Accepted Answer

Commercial schedules keep going through winter. A mason who lays on frozen units or with frozen mortar creates a wall that has to come down. Talk about keeping units and sand dry and covered, and heating mix water or materials when needed Mention enclosures and heaters for the wall, and protecting fresh work overnight Say you never lay on frozen or iced units and never use antifreeze additives unless the spec allows them Mention following the project's cold-weather plan rather than guessing

Question 6

Tell me about the heaviest block job you've worked on.

Accepted Answer

Wide units, split-face, and tall shaft walls are a different job from light partition work. They want to know how much weight and height you've handled. Name the building type: a school, a warehouse, an elevator shaft or a stair tower Say which units you laid and whether the walls were load-bearing or shear walls Describe the scaffold setup and how the crew stocked the wall Say what you learned about pacing yourself on heavy units

Question 7

What do you check when you're setting the first course?

Accepted Answer

The first course decides whether every course above it lines up. Mistakes here compound all the way to the top. Check the slab or footing against the layout lines and look for high or low spots Dry-lay the course, or at least check the bond, so cuts land where they should around openings Make sure dowels from the footing line up with the cells that will be grouted Set a full bed and get the course level before building up

Question 8

How do you work around other trades on a block wall?

Accepted Answer

Electricians, plumbers and steel erectors all need things built into your wall. Poor coordination means cutting into finished work. Describe checking with the electrician about conduit and boxes before you lay past them Mention setting door frames, embeds and sleeves as you go instead of cutting later Talk about marking the wall for the next course so nothing gets buried Give an example of catching a missed item and how it got sorted with the foreman

Question 9

What safety training do you have, and how do you work on scaffold?

Accepted Answer

Masonry crews spend much of the day on scaffold with heavy loads. Contractors want someone who won't overload a plank or skip guardrails. Name any cards you hold, such as an OSHA construction safety card Talk about inspecting planks and guardrails before loading block on them Mention not overloading the scaffold with pallets or mortar boards Say you follow the crew's rules for fall protection and silica dust when cutting

Question 10

Tell me about a time a foreman told you to tear out work.

Accepted Answer

It happens to every mason. They want to see if you own the mistake or argue. Pick a real example, such as courses out of plumb or a bar left out Say what caused it without blaming the tender or the line Explain how you fixed it and how quickly Say what you do differently now

Question 11

Why do you want to work for our crew?

Accepted Answer

Contractors lose masons to other crews all the time. They're checking whether you'll stay past the first cold month. Mention the kind of work they do, such as schools, warehouses or public buildings Say what you want to learn next, such as running leads or reading full structural drawings Be honest about what matters to you: steady work, travel distance or a path to foreman

Block Mason interview questions and how to answer them

The 8 questions you will almost certainly get

A forgettable answer, and a better one

"How do you keep grout cells clean while you're laying?"

"Walk me through getting a wall ready for a grout pour."

Questions to ask them

Need more Block Mason interviews to prep for?

The question	What they want to know	Your angle
How do you keep grout cells clean while you're laying?	Mortar droppings in a cell that's getting grouted cause voids, and the inspector can fail the pour. It's one of the clearest signs of a mason who knows structural block.	Say you keep the mortar bed off the cross webs of cells that get grouted
Walk me through getting a wall ready for a grout pour.	The pour is where a structural wall passes or fails, and a lot can go wrong between the last course and the pump.	Check that vertical bars are in the right cells, centered and lapped the length the drawings call for
What's a bond beam and how do you build one?	Bond beams tie a wall together horizontally. Getting them wrong can mean tearing out courses.	Explain it's a course of bond beam or knockout units with horizontal bars running through it
Where do control joints go in a block wall, and why?	Concrete block shrinks as it cures. Without control joints the wall cracks where it wants to, and that ends up on the contractor's warranty list.	Say you follow the drawings first, since the architect or engineer sets the spacing
How do you handle laying block in cold weather?	Commercial schedules keep going through winter. A mason who lays on frozen units or with frozen mortar creates a wall that has to come down.	Talk about keeping units and sand dry and covered, and heating mix water or materials when needed
Tell me about the heaviest block job you've worked on.	Wide units, split-face, and tall shaft walls are a different job from light partition work. They want to know how much weight and height you've handled.	Name the building type: a school, a warehouse, an elevator shaft or a stair tower
What do you check when you're setting the first course?	The first course decides whether every course above it lines up. Mistakes here compound all the way to the top.	Check the slab or footing against the layout lines and look for high or low spots
How do you work around other trades on a block wall?	Electricians, plumbers and steel erectors all need things built into your wall. Poor coordination means cutting into finished work.	Describe checking with the electrician about conduit and boxes before you lay past them