An example of Preventive Action & Costs

Example

 

The Existing Building
Brief description	Badly damaged (80%). Vulnerable to normal typhoon.
Foundations	Foundation walls: block cement with ring beam on 5cm concrete slab.
Structure	Bearing wall: block cement with cracks caused by settlement
Walls	Block cement walls without plaster, width=10cm, h=2.6m.
Works	Carpentry: wood in bad condition; Purlins and rafters: bamboo badly damaged
Roof structure	Carpentry: wood in bad condition; Purlins and rafters: bamboo badly damaged
Roof covering	Sheet iron
Doors & windows	Decayed wood
Total area / m²	22,2m²
Total value / Dôngs	6 660 000d
Value Dôngs / m²	300 000 d/m2

 

The Evaluation of weak points (compared with the 10 key principles of cyclone resistant construction) and identification of strengthening works

The Evaluation of weak points
Principle	Evaluation		Reinforcement
1. Location	Flat land		No change
2. Shape of construction	Rectangular		No change
3. Roof angle	30°		No change
4. Roof overhang, veranda	Without a veranda Roof overhang = 20cm and is resistant		Make new veranda with four reinforced concrete (RC) columns and rafters
5. Liaison between : Foundation - Walls -Roof	No connection between wall and rafters Unsafe connection between the wall and roof		New RC foundation for columns, reinforced ring beams for block cement walls. New block cement walls and posts with good connection
6. Triangular bracing	No bracing		Steel bar diagonal braces
7. Roof covering	Sheet iron Inadequate fixing of roof covering		Rafters and purlins joined with re-bar. Reinforcing bar on the roof
8. Opposing openings	Approximately		Opening the windows in the back wall
9. Doors and windows	Nearly destroyed (70%)		New doors and windows with locks
10. Trees (as wind breaks)	Few trees around the house		Plant more trees around the house at a safe distance
Global evaluation	Risk of typhoon damage		Reinforcement

 

Cost of Works
Item	Dongs
Initial value of the building	6 660 000
Works / Participation of the family	910 000
Works / Participation of DW	3 349 200
Initial value of the building	6 660 000
Works	4 259 200
Final value of the building	10 919 200
Final value / m²	491 855
Cost of reinforcement	4 259 200
% reinforcement / works	100%
% reinforcement / final value	39%