Terrace area crack filling || Waterproofing

[abhayms]

Hello Friends ...

Our 7 year old house has developed leaks.
During the last rainy season due to cracks in mould in terrace rain water had started leaking into the room below.

So on checking with some waterproofing agencies I got the below quote:
Rs 40 per sqft and the area that will be covered is 1200
Sqft

I was told the cracks will be filled and "Fosroc" RMX chemical will be used for waterproof coating.
The agency will give me a 7 year warranty as well

Could the gurus here please guide me if Rs 40sqft is a good rate?
Is there any other alternative?

Thanks for all the help
Abhay

[venk_pr]

Dear Abhay,

I am facing the same problem of fungus and cracks in the mould and water spotting in the room roof surface.
can u please provide me how did u get ur terrace fixed ? how much did they charge?
I got a quotation of Rs 100/sqft chemically filling all the cracks and using bitumat membrane, my roof area is around 800 sqfts.

If anyone have any idea regarding terrace waterproofing, please share your inputs.

I appreciate your help in advance,
Thanks
Venki

[ANUPKUMAR]

Instead of filling the crack you can put aluminium sheet on the top.So that you can use the terrace area in rainy season. Durablity is better than crack filling. In my house I am using it more than 15 years still it looks new.Cost is almost same or little bit higher than the crack filling

[ausraja]

ANUP how do you fix the aluminum sheet to the roof ? Just nail it to the roof is it ?

[ANUPKUMAR]

Many of the houses are facing the same problem either it is due to construction fault or material. But if we keep on doing the repair it never ends. we will end up with huge amount. If we use the aluminium sheet using polls and ankels even though it is little bit expense it protect the roof and you can used the area in rainy season, function etc. Or if your terrace is built with slope while constucting itself( like tile roofing) using angels you can easily fix aluminum sheet on the terrace itself.cost is less

[riturajmnit]

Hi Anup,

Please share the quotation details and vendor details.

Regards

[Nivas]

adding roof to protect a roof is over engineering , aluminium panels sits on top maze of ms support structure. it would cost you more erect it and to maintain it with regular painting etc. Chemical solutions\surface coatings are best , you can use pidilite Newcoat (3 coats) or similar in fosroc.
you can hire some painters to do the job , brush and vacuum clean \wet clean the surface and apply 3 coats at different angles. you can finish off with Brushbond cool roof for increased cooling . The PU \ UVR coatings are also available , these are more durable and expensive. anyways these coatings lasts long and are uv resistant. The coverage and quantity that need to be purchased is given in data sheets of these respective products .

[hegde19]

Nivas, how to take care of waterproofing for newly being constructed house?

[Nivas]

If your roof need to last long without leaks , keep advice from masons or contractors or builders or architects to a minimum. It does not need skilled labor nor it is expensive, however many make a living out of waterproofing contract jobs...
The chemistry is advancing so much that above will not be able to catchup, however yourself with direct contact with the chemical company can...customer care. they will be happy to help you aka BASF, Fosroc, Pidilite, Sika, MYK Laticrete, Ardex Endura etc . All of these companies have similar products for waterproofing, choice is yours, all of them sell products with good quality...

typically for a flat roof , the concrete slab will be parallel and flat to plinth . Top screed will be laid to create slopes for channeling rain water and give some protection.
Lets assume you haven't laid the top screed,
a) First clear the stuck debris with a wire brush and apply Brushbond TGP , this is a crystalline water proofing , The non soluble microscopic crystals grow into the cracks and crevices chemically over years and plug the leaks. The brush bond TGP is a cement like powder , but it is difficult to mix with water unless u have a paddle mixer. The next day after this coating , keep the roof moist for 14 days and never let it go dry for the crystal to activate and grow. if you miss this step it is waste.
b) Get Fosroc Brushbond RFX , and apply as suggested in data sheet. Leave it for day.
c)prepare the screed after b , while preparing the screed add fosroc conplast XR42ic to the concrete mix and mix Cement and NitoBond SBR latex to water , form a slurry and pour it over the roof . This forms a excellent layer. Typically the masons mix water and cement and pour the slurry before the screed laying. SBR is just a small addition.
d) After the screed is ready you can apply the Fosroc or Dr Pidilite New Coat equivalent or Berger Cool Cote equivalent.
e) if you need cool roof , apply Brush bond CoolRoof or similar with good Sun Reflectance Index. This formula contains nano glass spheres that reflect.

if you already have laid the screed , follow step d.

The material can be purchased from fosroc distributor directly. I know chirag agencies a major fosroc distributor in bangalore. You do not want skilled labour , just painters and helpers would suffice.download the data sheet and follow the instructions religiously .

[hegde19]

Nivas,

Thanks for very detailed info. Currently we are not there into screed stage. My contract reads out like below:

"Water proofing the roof slab with the following operations :
The first method consists of water proofing by surface method of average thickness110mm with waterproof admixture as per manufacturer's specification approved by Consultants with a minimum Guarantee period of 10 years. Cost to include – Cement slurry with waterproofing compound applied over the surface after cleaning the surface - Laying PCC 1:2:3 with water proofing compound - Joint less waterproof plastering with CM 1:2 mixed with water proofing compound and impression marking 300 x 300 Square with 3 mm rod /thread-markings. Treatment to continue along parapet for 300mmheight in shape of round wata, curing etc.,

The work should be carried out through a water proofing company approved by the Architects.. (Only Plan area shall be accounted)"

Quantity: 1,385.00 SFT
Cost: 1,17,725.00 (rs 85/- psft)

1. If we follow the methodology what you have suggested, what would be the cost?
2. In step "a" what is the right method to keep the surface moist? should we do ponding or use gunny bags and do periodic curing should be sufficient
3. Does the price quoted above does what you have suggested and is a reasonable quotation?

Thanks much