Thread: Vinyl siding stains

Any ideas why vinyl siding would leach "an excessive amount of" dirt through the weep holes? The siding in question is on the east side of the house, the entire east side of the house has the issue. The other sides are not as bad. The siding overlaps about one to two inches in most places and no overlap in a few places. The house appears to be wrapped. A 1997 house. No indications of staining on the wrap from the limited view I can get behind the siding. The overlap sections on the siding are dirt stained, the ledge on the back side of the siding has dirt in it. Could it be as simple as driven rain and field dirt? Adjacent homes built at the same time with the same siding do not show these signs. This is to a degree I have not seen before.

Similar Threads:

• Stains on the interior walls?
• Siding stains
• Siding Interface with Chimney
• Multiple siding layers
• Siding question

If you take the vinyl siding off a wall. There will be dirt, dust behind the siding.

That house sucks or blows, one or the other!

Most likely you will find no house wrap or some major areas missing in the wrap. This allows for air to either enter or exit the weeps on the siding and this shows in the way of the dark spots.

Originally Posted by Scott Patterson

That house sucks or blows,..

I sure hope the buyers don't read this. I had always thought of you as one of the nice guys here.

Thanks for the replies. Everywhere I checked had wrap. This is more excessive than anything I have seen before so I thought there may be some phenomenon I wasn't aware of. Thanks again.

30 years of working on houses and I never had any experience working with vinyl siding so when it comes to inspecting it....I'm always hesitant to start pulling and pushing on it because it always seems so brittle.

So how and where am I able to check for the wrap underneath while minimizing the chance of having a broken piece come off in my hand.

Originally Posted by Robert Foster

So how and where am I able to check for the wrap underneath while minimizing the chance of having a broken piece come off in my hand.

.
.
How to Use a Zip Tool - Vinyl Siding Removal Tool
..
.

Originally Posted by Robert Foster

30 years of working on houses and I never had any experience working with vinyl siding so when it comes to inspecting it....I'm always hesitant to start pulling and pushing on it because it always seems so brittle.

So how and where am I able to check for the wrap underneath while minimizing the chance of having a broken piece come off in my hand.

If the siding is installed properly it is hard to tell from the outside. You may be able to see the house wrap at the bottom just below the starter strip. I would not recommend removing any siding, if the siding is over 10 years (or more) old there is a good chance of breaking or splitting it, and if it is cold out even new siding could be easily damaged.

I think one of the best places, or maybe I should say safest places to check is in the attic where you should be able to find a big enough crack between the sheathing to see if there is any house wrap.

First, the Zip tool is a cool tool and as such I HAD to have one, once. Hey...I'm a guy! The reality is the Zip tool is more appropriate for large section removal which is unnecessary here. I used mine...once.

Simply start at an overlap joint and using finger tips, very gently peel loose the bottom edge of the top lap piece back about 6 inches or so along the piece. Just enough to peek behind. Do the inspection and then gently press the piece back in place starting from the opposite direction where it's still firmly attached. Provided it's not near freezing when performed the siding will yield easily roll and snap back in place nicely.

Next, it appears to me the discoloration could be an air borne fungus. The stuff attaches itself to the house and feeds on passing micro-organisms in the air. It does not feed on the siding material and is harmless to humans. It's the same stuff that discolors and streaks roofing materials.

That being said, I'd recommend a mycologist have a look at it for a final determination. If it is as I suspect, clean up is as simple as scrubbing with a light bleach solution.

Originally Posted by Bob Knauff

That being said, I'd recommend a mycologist have a look at it for a final determination.

I am wondering why you said the above before the latter?

If it is as I suspect, clean up is as simple as scrubbing with a light bleach solution.

Why not recommend 'cleaning it off' FIRST?

The above is like saying 'I think I need a 16d nail, but maybe a 12d will work - so recommend a structural engineer to determine what size nail is needed.

I'd just check for housewrap at the overlapped sections ("butt joint areas"). There's really no need to remove siding to do this. Just pull the siding out slightly at the overlap and peek in.

Perhaps I could have been more clear on that sequence Jerry.The recommended order of determining if it is a mold or fungus and what type and THEN cleaning it up, if possible, is very important. If it IS some kind of mold that may be a type that could be harmful to humans, for personal safety a mycologist or someone trained in the science needs to make that call. If they determine the discoloration is the type of benign fungus I have had experience with in the past, it can be easily cleaned off by the owner. But again, the expert has to make that call.

When reporting discolorations of this type I avoid calling it mold/mildew/fungus and so on because of course I am not the expert. I refer to it as a Bio-growth and always recommend an Industrial Hygienist or mycologist investigate it, indoors or out.

A good friend was messing around digging at the base of a tree in his yard about 2 years ago. Almost immediately he sensed his breathing passages closing up. He blamed it on a black dust that he disturbed near the tree and think it was a mold or fungus of some type that he breathed in a little bit of. Fortunately he recovered pretty quickly but now has to use a mild inhaler to clear his breathing passages on a regular basis.

That mold/fungus stuff is nothing to mess with, even outdoors and no matter how much or how little of it there appears to be!

Originally Posted by Bob Knauff

That mold/fungus stuff is nothing to mess with, even outdoors and no matter how much or how little of it there appears to be!

I disagree.

Otherwise we would not be safe DOING ANYTHING without first having some scientist come in and check what it is before we do it.

It is outdoors, use common sense and common protections (rubber gloves, face protector, etc., as needed) and use a bleach/water solution and wash the crud off. There is NO NEED to bring in a scientist to test it and then say, yep, use bleach and water to wash it off.

Each of us has a different tolerance for pain Jerry but would you put that advice in writing in a report to a client? I wouldn't! Matter of fact, I wouldn't even tell them something like that "off the record" !

My inspection yesterday had vinyl siding and since no client or Realtors were in attendance I figured I'd give separating the vinyl a try. Man...you could unzip the whole house in no time. I checked in six different locations and all had house wrap undeneath. Not sure I'll do this as standard practice, but maybe if I don't see wrap at the bottom of the wall I'll investigate further in this manner.

Thanks for the replies.

Yup, it's pretty easy to do! In fact it gets easier. You needn't even loosen the top piece to see if the house is wrapped. Just gently pull the top piece out away from the bottom piece at the lapped joint edge, without unzipping it, and shine a flashlight in to see if it's wrapped under there. It's common to not see wrap sticking out at the bottom of the wall but be in place anyway.

An added benefit of this exercise is to make sure the vinyl is over lapped more than a couple of inches at the joint that it needs to accommodate for thermal movement. Too many times I found laps of 1/2" or much less. Great spots for wind driven rain and snow to enter! Once in a while a bit of water would even run out or the substrate would be wet in a pattern consistent with rain or sprinkler water being driven into the lap joint, when I peeked in.

One word of caution when doing this type of investigating however. Real estate agents HATE it when you bring up the issues of no house wrap or inadequate over lap of panels or moisture behind the vinyl and so on. Be VERY prepared to back up your findings. An outstanding source for vinyl siding installation best practices is published in the Vinyl Siding Installation Manual by the Vinyl Siding Institute (VSI) at: Publications - VSI - The Vinyl Siding Institute. Most installers need to read the stuff they have to offer because 99.9% of the installs I looked at are incorrect in one fashion or another, at least according to their own overseeing trade organization!

Thanks for the link...I actually have a copy of that vinyl siding installation manual. The below section is why I consider myself fortunate for not having to work with this material any in my carpentry days.



Vinyl siding has always been designed as an exterior cladding, not a water-resistive barrier. Vinyl siding is designed to allow the material underneath it to breathe; therefore, it is not a watertight covering. Because of its design and application, it provides a supplemental rain screen that enhances the water-resistive barrier system by reducing the amount of water that reaches the underlying water-resistive barrier.

I think peeking through the overlap is a better idea...unzipping it is a little too invasive for my taste....especially if you have an audience of clients and Realtors. I here you about Realtors....oh well....I've already had to tell one if your looking for a deal facilitator I'm not your man.

Yeah, Robert, vinyl siding is interesting stuff. Your quote from the manual is exactly the reason I make it a point to show my clients some of the little weep holes in the bottom edge of a piece of siding material on their new home (as seen in the original post images) and explain to them that even the VSI says moisture WILL get behind the stuff and try to impress upon them the need to monitor the walls and siding material for damage PARTICULARLY if the home is not wrapped. Again, sometimes to the chagrin of the agent!

Bob....are you saying when you find a vinyl sided house without wrap you write it up as a maintenance item to be monitored ?

I have another plastic wrapped house today.

Originally Posted by Robert Foster

Bob....are you saying when you find a vinyl sided house without wrap you write it up as a maintenance item to be monitored ?

I have another plastic wrapped house today.

If I'm not mistaken house wrap was not required under vinyl till around 2006. This is one reason we see so many homes without it. My entire neighborhood has no house wrap under vinyl, most homes were built between 2000 & 2007.

Scott is correct. Wrap was not required for many years and even after it was required the further out from a metro area one got the more lax the enforcement.

I finally came up with this stock comment for my reports.It is designed to protect and inform the client as well as cover me in case there is damage I could not see or easily find.

"POINT OF INFORMATION: The building is clad in vinyl, lap style siding applied horizontally. Although it may have been proper at the time it was built, today's good building practices as well as vinyl siding manufacturers dictate the house be clad or "wrapped" with an approved moisture barrier before the vinyl siding is installed to help prevent moisture intrusion and possible damage to the building as well as help avoid mold and mildew issues. A random sampling on at least two exterior walls of the house by lifting the siding material at a lap joint revealed no wrap material under it so it is safe to assume the entire house lacks that protective moisture barrier. The wall sheathing under the vinyl is a fiberboard type material that will deteriorate very rapidly if allowed to get wet.

If the vinyl siding flashing around windows and door openings was installed properly as described in the CertainTeed, Ashland-Davis - Installation Instructions, Basic Installation Guide: Part1 and 2, that can be read at: CertainTeed – Manufacturer of Quality Building Products

there is a chance that excess moisture can be kept off the sheathing at those critical points and help avoid problems for the time being but sooner or later, there may well be moisture entry and deterioration. Unfortunately, we have no way of knowing what time frame that involves. It can be very weather dependent. If the flashing has not been installed or is installed incorrectly (we have no way of knowing without removing pieces of the siding) then rain water that is directed away by channels at the tops of doors and windows will run down the side channels, saturate the sheathing and cause damage rapidly. None-the-less, the rest of the wall areas are still left unprotected and subject to moisture intrusion also.

Randomly moisture testing interior wall areas around some windows and doors did not detect any elevated levels. No moisture staining was noted in these areas at the time of the inspection either.

NOTE: Be aware that if you accept the lack of house wrap/moisture barrier as part of the home buying transaction you will be accepting responsibility for damages and/or repairs as/if needed in the future. Please monitor the siding and walls regularly for signs of moisture damage and take corrective action immediately to avoid problems."

Many, many homes stood for years with no wrap and no damage and there's the rub with agents. They jump on that like flys on... something! However, who's to say that the following day or week moisture wil not find it's way behind the vinyl and suddenly you have a problem. Who are they going to call then?!

Also, the critical points of the siding installation are channels, or lack of them, around doors and windows that can direct run off behind the siding. It's been my experience that these are almost never done correctly. Now what do you advise your client?

I lifted some drawings from the VSI manual showing proper channel installation and use them in my report as an example. A picture is worth a thousand words and the clients then are able to view something they understand and can relate to a contractor.

But the owners need to know that if a hole is punched in the siding by hail or lawn mower thrown rocks and such, or a piece of siding is blown loose or off, it needs to be repaired immediately to avoid moisture intrusion. If you decide to travel this road be prepared to spend time educating the client and assuaging fears about the situation.

I could go on and on but we are creating a large thread drift. Good luck!