Buildings decay for several reasons: climatic issues like sunlight, moisture, wind, and temperature fluctuations cause fading, cracking, erosion, and structural stress; botanical issues like plants growing in walls absorb moisture and cause damage; atmospheric pollution from industry and vehicles accelerates the natural weathering process. Poor construction, improper repairs, and neglect of maintenance also contribute to building failures over time.

1. failures
NAME:R.KIRAN KUMAR REDDY
ROLLNO : 12061AA005
CLASS : V SEM

2. CAUSES OF DECAY and damage OF
BUILDINGS

3. WHY BUILDINGS DECAY
• because of the following reasons:
• CLIMATIC ISSUES..
• BOTANICAL and BIOLOGICAL ISSUES..
• INSECTS and ANIMALS
• ATMOSPHERIC POLLUTION..
• POOR CONSTRUCTION,INAPPROPRIATE
REAPAIR and NEGLECT..

4. CLIMATIC ISSUES..
(SUN)
• SUNLIGHT:
- UV is particularly damaging on organic materials such as
wood,textile,pigments etc..
• Causing colours to fade and surfaces to beocme brittle.
• Peeling of paint from the walls,being caused by it.
• THERMAL EXPANSION:
Building materials expand when heated and contract
when cooled.
• As a consequence,stresses can build up between the individual
materials and the buildings as a whole.
• Seasional temprature,amount of sun,wind and rain falling,all
contribute to overall thermal movement.

5. DAMAGE TO UNTREATED WOOD
CAUSED BY THE SUN
COLORS FADED

6. Climatic Causes –
(Moisture)
• “Faulty disposal of rainwater is the most frequent
cause of deterioration in ancient masonry”
•Rainwater washing against the surface of a
structure,will gradually wear it away
•Mortar and porous masonry are particularly vulnerable
•Rainwater penetration into the individual materials
of the structure causes more damage through:
•Salt crystallisation
•Continual wetting and drying
•The action of frost and ice

7. Moistue causing seepages on walls

8. Climatic Causes –
(Wind)
• Wind can exert a strong directional force..
•The exposed side of a building can therefore be subject to a “pushing”
action, while the protected side can experience a “suction” .causing the
walls to displace...
•Towers, spires and bell towers can move in high winds.
• Wind disturbes the general external erosion of most
building materials ..
•Roof coverings (eg. tiles, slates, lead and copper sheet) can be lifted in a
high wind

9. Botanical issues
• “creeping” plants can damage masonry if unchecked .
-- plants growing in masonry cause disintegration of the material.
• If forcly removed it can pull off a weak surface of brickwork or plaster
•Climbing plants can be grown on frames or wires attached to walls
•The presence of plants growing in a wall is usually an indication of
decayed mortar and excess moisture
•Large plants or shrubs growing at the base of walls can trap moisture
and their roots can damage underground drains
•Trees near buildings can undermine their foundations and cause
ground heave
•In clay soils trees can withdraw ground moisture causing the
surrounding soil to shrink,thus causing movement of the foundations
and subsequent cracking of walls

10. PLANTS GROWING ON WALLS

11. Atmospheric Pollution
• Naturally weathering cause stone
to deteriorate over many
thousands of years and bricks
over several hundred
•This process is accelerated by
pollutants released into the
atmosphere
•Oxides from the burning of coal and
oil
•Nitrogen from vehicle exhausts
•Direct contact with wet stone of
pollutant particles can also cause
severe decay (acid deposition)

16. decay
 Blocked rainwater pipes, peeling paint and plants growing in gutters are
the inevitable causes of building failure
 The most common causes of building failure can be traced to one of
three causes — poor design/construction, inappropriate repair or
neglect
 The weather also plays an important role in the decay of the
structures