Inspection (L3) Head Farm

Question 1

Talk me through the project, what was the issue?

Answer 1

The issue was to the West elevation of the property in which rainwater was finding its way into the property leaving staining on internal finishes and if left unresolved, the rainwater ingress could cause damage to other elements of the property.

Question 2

What other elements of the building might be affected if the issue was unresolved?

Answer 2

• It was evident from my inspection the internal leaf lintel was timber. Overtime if left unresolved it could cause timber decay.
• With the walls being persistently damp the retrofit installation would clump and possible slump within the cavity leaving cold spots. This could cause condensation issues.

Question 3

Why did you advise intrusive investigations were required?

Answer 3

• Based off my visual inspection I noticed there was missing mortar to the brickwork to a large proportion of the west elevation in which the staining was evident.
• Furthermore, I could not see any weep holes above the window which would suggest a cavity tray was not installed.
• For this reason, I advised removing some of the brickwork to expose above the window and to the side where I would expect to see a lintel.

Question 4

What did you find once you removed some of the brickwork?

Answer 4

• I found that there was no cavity tray installed and no weep holes. The cavity had been filled with a retrofit insulation which was wet.
• I was able to identify a steel angle lintel which was significantly corroded.

Question 5

What was the impact of the corrosion to the steel lintel?

Answer 5

• The corrosion would cause the steel lintel to expand causing the brickwork to lift and creating a gap at the top of window frame allowing rainwater to also find its way into the property

Question 6

How did you go about producing a budget estimate for your client?

Answer 6

• For the intrusive investigation I used agreed rates from our term service contractor and estimated the work would not take any longer than one day to remove a couple of bricks and reinstate.
• I used rates from a colleague within the housing department who had a carried out numerous repairs of a similar nature for producing my report for the client with costs and recommendations for remedial work.

Question 7

What recommendations did you provide your client for the repairs?

Answer 7

For the remedial repairs I advised removing the brickwork and replace both the inner leaf timber lintel and the external leaf steel lintel with an appropriate size catnic lintel allowing for 150mm minimum end bearing.

• On reinstatement, I advise installing a cavity with weep holes and cavity insulation
• I also advised to repoint the whole West elevation.

Question 8

What did you consider for the accuracy for your budget estimate?

Answer 8

• Time
• Cost
• Quality

Question 9

Did you consider any other option for carrying out the inspection?

Answer 9

• I used a borescope and inspection camera; however, the property had retrofit cavity insulation which was difficult to identify what was going on within the cavity.
• There was no other practicable means of investigating with a solid evidence for the cause of the rainwater ingress.

Question 10

How did you know it was corroded?

Answer 10

• It was visibly clear. The original steel thickness was 10mm. The steel end was beginning to delaminate.

Question 11

How did you establish the source of rainwater?

Answer 11

• During the inspection it was dry but windy. I asked the contractor to soak the elevation wall with his onboard jetter. A few minutes later the water began to find its way into the property.