Sealing around deck screws

[Rocky98Formula]

My parents have a deck with a garage space under it at the back of their house. This deck was built over 25 years ago and uses a couple inches of concrete as the deck surface. The way the deck was built, water has always made it's way down into the wood frame that supports the deck. So much so that at one point 15 years ago the entire supporting wood frame structure had to be replaced because it had completely rotted (deck surface supported on jacks and walls rebuilt).

Eventually we managed to vinyl wrap the concrete surface and add flashing and gobs of sealant to prevent water from making its way down into the frame. It held up well for over 10 years like that. However, my mom recently replaced the deck railing with new aluminum rails and the installers ended up using screws through the vinyl into the concrete to secure it as seen in pictures. Needless to say, water has started making its way through the deck again. Any suggestions on the best way to seal this mess? Ultimately we need to seal between the aluminum base pads and the vinyl as well as around the screws? Is there a type of sealant that would work better than others? The house is in Vancouver where it rains and rains but usually no snow.

 

[blacksporty]

I would loosen the screws so you can get sealant under the rail posts, once that is done and screwed back down I would then reseal the screws and the rail bottom. For the sealant I would probably use Dicor, which is an RV roof sealant, it is pretty good stuff lasts on RV roofs for years and if you see any cracking you just clean it and go right over the top with another coat.

 

[kd3pc]

Dicor is for a specific "rubber" roof product and is fairly pricey. It only works on rubber roofing that has not been sealed with any other (silicone, etc) contaminate. Been there and done that.

I would call the contractor/vendor who did the work and tell them to properly "bed" these anchors, as there are quite a few butyl rubber products (often used in the marine/boat industry) that will stop the leaking......they should have done that before...

I would suggest not using them again.

If they won't make good, then you have no option but to "bed" those rail posts and the hardware used to attach them....

 

[Jess]

It looks like they sealed the top of the fasteners with silicone. Might work for some things but not a good effort if there isn't any under the post flange. In our wet climate, I have had good success with Sikaflex polyurethane marine caulking, available at places like Steveston Hardware and Marine or any decent marine supplier over there. I would also consider looking up Ducan who make vinyl deck sheeting products and see what they recommend or call them. http://ducan.com/contact-us/default.php Whatever you use, clean under the posts, dry and mask out and area because it will squeeze out and make a big mess if you are not careful. Sikaflex is available in various colours to suit what you are doing. Any product will need maintenance after years but would be easy to do again 10 yrs from now.

 

[Rocky98Formula]

Dicor is for a specific "rubber" roof product and is fairly pricey. It only works on rubber roofing that has not been sealed with any other (silicone, etc) contaminate. Been there and done that.

I would call the contractor/vendor who did the work and tell them to properly "bed" these anchors, as there are quite a few butyl rubber products (often used in the marine/boat industry) that will stop the leaking......they should have done that before...

I would suggest not using them again.

If they won't make good, then you have no option but to "bed" those rail posts and the hardware used to attach them....

Thank you everyone for the suggestions so far. Kd3pc, the contractors are not taking any responsibility for this and I've given up hope of getting them to come back on site. When you say to properly "bed" the anchors, what exactly does that entail? I was thinking of following Jess' recommendation and maybe trying some rubber washers to seal the top of the nuts?

 

[kd3pc]

Jess is on track - he describes "bedding" very well, I use a good marine sealant or butyl rubber under and between the post, then another coating on the fasteners. Let everything relax and seal over, then tighten the bolts. Top the bolts with another layer of butyl or Sika.

Should last years.

I understand how the contractor works...that is where I learned all about Dicor...the hard way.

 

[Ruthless53]

get some 5200 sealant, put some gloves on, seal it up.

May want to tape over anything you really don't want glue to get on because once its there its really there.

 

[Jess]

A bit of research will help you choose the correct product to meet your expectations. 3M 5200 is mentioned and has extreme holding capacity. Its also difficult to remove later. We use 3M 5200 to attach mounting plates underwater on fibreglass boats in order to avoid drilling holes in the hull. The plates are tapped for bolts or screws and hold transducers in position. Great stuff for that use and many others.

 

[Kpaige]

I did not read every post so forgive me if this was said.
This needs to be ripped down to the deck fix all wood then put a fully adhered reinforced epdm fubber membrane with perimeter flashings etc. Then th deck should be built in 2x2 or small sections and set in place on protection matts. The railing should be fastened to the exterior wall not through the roof.