Mock Interview (DeLever) - Case Study

Question 1

Explain to me what had caused the failures?

Answer 1

There was lack on connections to the apex, extensive corrosion to the steel stole plate and what appeared to be numerous repairs to all the portal frame columns at the base. Mostly likely due to timber decay, as the glulam beams were partially exposed externally.

• two decades worth of on-going repairs

Question 2

Was it purely the connections which was the cause of the defect?

Answer 2

The problem was the portal frame was partially exposed externally. The soleplate was also found to be slightly lower than ground level.

Question 3

How old was the structure?

Answer 3

1970’s

Question 4

On the ridge line was it bowing slightly?

Answer 4

Yes.

Question 5

Thinking about your options for construction, you considered modular; have you used modular construction before?

Answer 5

No.

Question 6

Looking at modular construction, what do you think were the real key benefits to that option?

Answer 6

• Majority of the manufacture was done off-site reducing the on-site construction programme and minimising any potential health and safety issues.

Question 7

Was the new building that exact same footprint of the existing?

Answer 7

Within the existing footprint but a smaller building.

Question 8

Did the school need the hall?

Answer 8

The hall was privately funded and was being use at one point as a nursery building. However, circumstance’s changed and the building was used as teaching space for the early years children

Question 9

You have explained your role, what parts of the design were you responsible for?

Answer 9

I design the floorplan, external play area including the canopy and footpaths.

Question 10

How did you connect the extension to the existing building?

Answer 10

I installed a vertical timber plate to the existing buildings and slot with the timber frame walls to allow for movement.

It was a connection that allowed for settlement and extension between the masonry and timber frame buildings.

Question 11

You discounted the modular building because the lane was narrow and large trees. Could you have had the modular building delivered in smaller sections to site?

Answer 11

Yes the sections could have been smaller, however there was still the issue of the mature trees to the boundary. You would still need to close the road for a crane. However, there were overhead power cables which were also a concern.

Question 12

How did you get the timber frame panels in?

Answer 12

Timber frame panels were delivery on a low-load vehicle. They were delivered in the same manner as roof trusses.

Question 13

Did you need a crane on-site for the installation of the panels; what about the roof?

Answer 13

The panels came in sections of 1200 x 2600mm and were lifted in to place by two operatives. Small modules.

The roof trusses were lifted into place by a tele-handler.

Question 14

The timber frame itself, when that was procured, were there any specific payment terms; did you have to pay for it up-front?

Answer 14

No.

Question 15

How did you cost the three options?

Answer 15

• The repairs were costed on time and materials
• The modular was costed on previous rates from my colleagues accounting for location and inflation.
• The timber frame was costs from the previous years rates accounting for location and inflation.

Question 16

What was the cost of the three options?

Answer 16

• £100,000 for a full repair and refurbishment
• Modular classroom was around £125,000
• The new extension was around £250,000

Question 17

How did you provide this advice to the client?

Answer 17

I provided my advice to the client within a report with an options appraisal.

Question 18

Take me through the tender process for the timber frame?

Answer 18

I used a performance specification for the timber frame ensuring compliance with all aspects of the building regulations. I then procured the scheme on the NEC3 Short Contract.

Question 19

Why did you advise the client to use the NEC3 Contract?

Answer 19

I used this contract because it is standardised within our department primarily for consistency with regards to the terminology.

The JCT Minor Works contract would have also been a suitable option due to the size and nature of this scheme.

Question 20

You have a strange figure in for liquidate damages; how did you calculate that?

Answer 20

We have a system which we use to calculate liquidated damages to ensure consistency across our department.

It is not something that I do personally. I am aware there is a formula you can use.

Question 21

Could you have had the services contained within the panels off-site?

Answer 21

Its not something I considered.

I am aware that it is something that would be possible but not something which would have saved a significant amount of time for this scheme. Perhaps it would have been a better option for a larger scheme and something I will consider for next time.