Building Pathology Level 3 - North Ferriby Primary School

Question 1

Describe the initial defects you saw?

Answer 1

Previous repairs

Standing Water

Spongy Feel

Defective Flashing

Defective Rooflights

Question 2

How did you establish full extent of the problem?

Answer 2

Plotted extent on a drawing/ plan of the building to establish how widespread the problem was.

Core samples taken at various points at different levels of the roof.

Question 3

How does leak detection testing work?

Answer 3

Types Wet/ Dry

Dry - Roof, dry, push brush over audible alarm will sound whenever water entry point is found.

Wet - Cable around the perimeter of the roof - Electrical field pulses identify water entry point. Roof must be wet (post rain or simulated with a hose or similar)

Question 4

What other types of testing could you use to identify water entry points?

Answer 4

Thermal imaging camera

Identify temperature changes. Tends to be warmer colouring in water entry points

Question 5

How would you interpret the results from the thermal imaging results?

Answer 5

By colour - higher temperatures red/ white colour. Lower temperature = blue/ green

If widespread doesn’t always identify the exact source but may identify probably locations to allow for a closer inspection.

Question 5

How would you interpret the results from the thermal imaging results?

Answer 5

By colour - higher temperatures red/ white colour. Lower temperature = blue/ green

If widespread doesn’t always identify the exact source but may identify probably locations to allow for a closer inspection.

Question 6

What type of defects would you expect to find if leaks went on for a long period of time?

Answer 6

Deck/ Joists may suffer from a type of rot either wet or dry rot.

Flaking damage to internal ceilings textured coating.

Damage to decorations

Question 7

How did you advise your client?

Answer 7

Roof beyond serviceable life and requires renewal.

Temp repairs to be carried out to slow/ stem leak over the winter period.

Lack of information regarding asbestos within textured coating ceilings (advised R&D survey)

Specialist contractor to remove part of the ceiling.

Question 8

What was the long-term advice?

Answer 8

Renew roof coverings

Remove back to deck (check condition of deck) - Replace roof coverings

Tapered insulation system. Single ply membrane

Question 9

Why do you think school buildings initially begun to use internal rainwater pipes?