Is terrace waterproofing needed?

[rsk]

Hi All,

Happy to find this forum on civil construction and would like to thank people who are giving their advice to all.

We are constructing a house and need to decide on terrace roof water/heat proofing. To give you an idea this is where we are at w.r.t our house: 6 months back our roofing was done and our house is in the completion stage now. The outside walls has got one coat of white cement done and inside walls one cost of painting done the final coat of paint is pending. The roof ceiling is plastered and one coat of white wash has been done.
Below are my questions:

1. Recently there were rains and water stagnated for 2 days on our roof top terrace, due to this I could see dampness in 4 to 5 spots on the ceiling (bottom roof). Shouldn't the new rcc roof not take in dampness as it is RCC... or is the construction or material used is sub-standard or any other reasons? I did not expect this on new roof. The walls also had dampness on them. Does this dampness or leakage occur to all the buildings in the 1st year since it is a new building. Will these dampness/leakage be arrested after going trough one weathering cycle (1 rainy and summer season). Or is it a construction defect with material or workman ship problems?

2. Why olden days nobody thought about waterproofing and only cement screed or brick bat coba was done to provide slope? was that sufficient enough to protect the roof top?

3. If we need to waterproof, there are commercial products like Dr.fixit, ardex endura etc... Which is best in terms of durability, maintenance, cost. Has anyone tried these products/methods before and what is your experience over the years?

4.On top of cement screed is heat proofing needed. If so any recommended method that you have tried? Is there a chance that over years because of hot weather these days, heat can transfer and cement screed inside roof plastering or roof either of these can crack.

5. If there is not going to be any further construction above the roof in the next 5-10 yrs then what are the best options/recommendations to protect the terrace. We came across the following options.
a)Just provide concrete screed with good slope.
b)Apply waterproof coating and put cement screed with slope.
c)Apply waterproof and put tiles
d)Apply waterproof coat and put brick bat coba method.

Please provide your inputs/comments.

[Nivas]

there is already a detailed thread "Terrace area crack filling || Waterproofing" with most your questions answered http://www.mybdasites.com/viewtopic.php?f=36&t=5579

[rsk]

Thanks Mr.Nivas! The link was useful and answered some of my questions.

[Naresh Patel]

Hi All,

Happy to find this forum on civil construction and would like to thank people who are giving their advice to all.

We are constructing a house and need to decide on terrace roof water/heat proofing. To give you an idea this is where we are at w.r.t our house: 6 months back our roofing was done and our house is in the completion stage now. The outside walls has got one coat of white cement done and inside walls one cost of painting done the final coat of paint is pending. The roof ceiling is plastered and one coat of white wash has been done.
Below are my questions:

1. Recently there were rains and water stagnated for 2 days on our roof top terrace, due to this I could see dampness in 4 to 5 spots on the ceiling (bottom roof). Shouldn't the new rcc roof not take in dampness as it is RCC... or is the construction or material used is sub-standard or any other reasons? I did not expect this on new roof. The walls also had dampness on them. Does this dampness or leakage occur to all the buildings in the 1st year since it is a new building. Will these dampness/leakage be arrested after going trough one weathering cycle (1 rainy and summer season). Or is it a construction defect with material or workman ship problems?

2. Why olden days nobody thought about waterproofing and only cement screed or brick bat coba was done to provide slope? was that sufficient enough to protect the roof top?

3. If we need to waterproof, there are commercial products like Dr.fixit, ardex endura etc... Which is best in terms of durability, maintenance, cost. Has anyone tried these products/methods before and what is your experience over the years?

4.On top of cement screed is heat proofing needed. If so any recommended method that you have tried? Is there a chance that over years because of hot weather these days, heat can transfer and cement screed inside roof plastering or roof either of these can crack.

5. If there is not going to be any further construction above the roof in the next 5-10 yrs then what are the best options/recommendations to protect the terrace. We came across the following options.
a)Just provide concrete screed with good slope.
b)Apply waterproof coating and put cement screed with slope.
c)Apply waterproof and put tiles
d)Apply waterproof coat and put brick bat coba method.

Please provide your inputs/comments.

With the quality of the building materials being used in construction these days and the tropical weather that we have in our country, I would have to say that waterproofing is absolutely necessary! It’s always better to take precautionary measures rather than having to fix a much larger problem later on. When my bungalow was first built I ensured that the contractor carried out waterproofing on our cement roof. Thanks to that one decision, I have never faced a leakage problem from my roof. I would strongly advocate it since the quality of the buildings, materials and structures isn't the same as it used to be in the olden days. If my memory serves me right, my contractor used a waterproofing compound called Roff Hyproof. Apparently it is one of the best solutions for terrace waterproofing as well as concrete, basements, water tanks etc.

[Vishnu2014]

Please make sure you do the following:

-> Water proofing in the terrace must be done
-> Also make sure that you put tiles and water proof grouting between the tiles
-> Proper grading so that water flow out through pipes and doesn't stagnate

[rsk]

Thanks Vishnu for your inputs! We have decided to do waterproofing and put a cement, aggregate layer on top with good slope to drain water.

[rsk]

Thanks Naresh for sharing your experience!

[vsivakumar]

Slopping in Terrace is Must
Even Parapat walls Top surface needs to be Slopped
Slope in Ventilator coverring Windows also needs to slopped
Provide sufficient outlet pipes in Terrace to drain out water immediately - If needs provide 2 or 3 outlets in terrace
See that no water is stagnated in Terrace.

Cool Roof tiles are available in the market at Rs.50/- piece you can try this or leave the Terrace with simple Screed mixed with Waterproof chemical.

Siva-Chennai