How to Seal betw Stepped Brick&Vinyl siding

I discovered that rain enters my house through a vertical gap between vinyl siding and my stepped brick chimney. Bought my house last year. After a heavy rain, a moisture meter found dampish drywall indoors next to fireplace and there’s efflorescence at a few spots on interior fireplace brick. Also a wood stud behind the drywall was rotted probably from long term water. Under the exterior vinyl siding is the original asbestos shingle siding. I’d appreciate recommendations about the best procedures and materials for preventing water from entering the wall. I already had chimney company seal the chimney, add a new chimney crown, seal roof flashing around chimney, add new tin “hat” on the crown. Chimney specialist said the rain entering my house is not his bailiwick, that I should hire a “siding guy.” I want to understand the correct procedures and best materials and what kind of professional is best choice to do this work, before I hire someone. Chimney and siding are on the south side of house. Many thanks.

Pictures would help to understand exactly what you are talking about…

You may only need a simple tube of silicone caulk. This joint is known to be problematic for air infiltration on older homes so it is not surprising that water would follow.

The original joint between house and chimney should be sealed first. From there you have the choice of installing several types of flashing which would extend behind the vinyl siding and over a few inches of the brick. This flashing would be sealed between it and the brick with - you guessed it - silicone caulk.

The flashing may or may not be necessary, but an experienced general contractor would be a better option than a siding company.

Curious, what area are you located in?

Agree with an experienced GC. At this point, it sounds like the siding will need to be removed in that area, and all damage repaired. Without knowing what repairs will be needed, a GC will handle all the trades needed, as long as that is stated in your agreement with him/her. Make sure he gets any permits that may be needed, and all inspections are performed. You need to be proactive here.

I personally have always preferred a polyurethane sealant like Vulkem for this type of application over silicone. :smiley:

Good call.

I’ve been a fan of Vulkem for many years, many times it will outlast the material you put it on. Warning, do not get on hands or clothing. :smiley:

Agree not because it is a better product but because it adheres to brick better than silicone.
I usually advise urethane on brick for that reason.

Thanks for the clear discussion, everyone. I’ll try to add photos to this posting. I’m new in this town (in Maryland), I’ve had some difficulty finding the right people and also many companies don’t want to do small jobs. Also for some work I’ve had done, a couple tradesmen overcharged wildly (learned in hindsight). So it’s good for me to know exactly what to ask them and what’s the right way of doing it. I have a trustworthy friend who could do caulking carefully, but my guess is that installing flashing correctly requires someone with building experience. I took photos of each side of chimney (at the time one side was in shade). While taking pics, I noticed that the “J” channels look a little whacky – I wonder if the channels were installed right and whether they’re directing water correctly. I’d appreciate hearing if the photos reveal something more I need to know to accomplsih the correct fix. Thanks again.

Here’s another photo because the other photos I uploaded don’t show the definition of the chimney steps that abut the house wall. The vinyl siding can’t be snug up against the chimney sides because of the steps of course.

Until its properly stepped flashed and counter flashed your going to have an ongoing problem…simply caulking it every 6 months will get old.

Siding needs to come off and proper flashing needs to be applied…once that is done you will never have to worry about using caulking.



Ditto…best advice so far. I hate vinyl siding and we have a ton of it here, usually installed poorly or completely wrong. Missing flashing is the number one discrepancy, followed closely by inadequate flashing or flashing that actually creates a problem (directs water behind the vinyl and into the interior of the wall transition points.

Thanks. What kind of person would be best experienced to do this work? Maybe a home improvement contractor who has been in the business for a long while? One more question if I may: What kind of flashing is correct to use on the vinyl siding and the chimney bricks (including the stepped brick shoulders)? Really appreciate it.

A GC who is willing to take responsibility in case it leaks…one who actually knows proper flashing techniques.

As to kind of flashing…leave it to a professional who can actually look at it versus us taking an educated guess based upon pictures.




Caulk is a temporary repair, Flashing is for permanent water diversion when installed properly.

Its hard to find someone who actually knows how to install Flashing, but if they own a Brake, chances are greater they will install what they make correctly.

VSI Certified Installers

Vinyl Siding Installation Manual

It may also be a lead flashing which can be molded to the brick. Find the old guy in the phone book or his son.

Thanks to both of you. I had to look up brake of course. Another thought I had was to get some sort of chimney “shoulder slabs” installed over the stair-stepped bricks (by a professional). so that then flashing could be installed in straight lines. But that would probably cost more than getting the flashing and counter flashing on the brick steps. I’ll look for a contractor who owns a brake and ask.

Wow, I’m loving all this information. Thanks to all.

Where is Frank Albert when you need him?

Probably fixing leaks!!

He might know of someone up that way.