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Leaks, condensation, debris, flashing problems
Our home is 4 years old with 5V galvanized metal roofing. We have encountered serveral problems: 1) Since the first winter we've had problems with drips in the late mornings, especially after a freeze, and mainly from the cathredral ceiling over the living area. Our contractor initially seemed to think this was "normal," and recently told us it is from too much heat rising into the attic from the whole house fan in the upstairs hall. 2)This summer we found water stains in several places upstairs in the hall and in the bedrooms. An inspection revealed much debris over the insulation in the attic plus evidence of rain leaking down the rafters after a hard, wind-driven rain. 3) When we have a good rain, water runs down the hearth of a stone fireplace on the screened porch. The contractor said the mortar needed waterproofing, but an inspector suspects improper flashing. 4) Additionally, there are water stains all over the wooden ceiling of the front porch. There is blown-in insulation in the attic and insulating poly panels over the cathredral ceiling. There is no vapor barrier. The metal is screwed to rafters with no plywood or felt underneath. There is soffit ventilation and 2 small gable ventilations. There is not a ridge vent, only a ridge cap. Our insurance will cover repainting only and our agent suggests we get accurate installation information from a reputable source before approaching our contractor again. Can you PLEASE HELP??
It would help to know the location and roof configuration like pitch, rafter length etc. however here goes.
I assume by your web address that you are located in NC. I suspect that you have all the concerns you mentioned to some degree. Definitely you have poor ventilation coupled with no vapour barrier. As you are in a climate that has interior temperatures above the outside this is an important element that keeps the warm air inside. As it is it migrates out condesing as it cools and will form on the underside of the roof as you have poor ventilation and no moisture barrier under the roof.
With a 5V profile the condensation will run down the underside of the metal until it hits a strap and then it will drip. As well if your pitch is too low the 5V profile is weak in this regard and coupled with no maoisture barrier and poor vrntilation you could have the wind ingest the water into the roof system with a vacumn.
As to the chimney flashing more times than not it is a poor flashing detail however if a cheper brick was used of field stone they can soak up the water and bypass the flashing. An easy way to check is with a good ol garden hose. Start at the bottom of the chimney and work up each side and then acros the top with someone inside lokking for leaks. Do not go more than 1" above the flashing. If you still do not locate it start up the chimney in the same pattern about 12" at a time. Soonner or later you will locate it.
As to a cure for the other, I would suggest checking all the fasteners in the suspect areas especially any that appear too tight. Also look for stressed or bend side laps. If the slope was too low you could unscrew the joints and put a small bead of caulk in and retighten. Next open the ridge up and install a vented ridge either with vented closure strip of vented metal.

This will help treat the ailments. If you need more advice contact me directly. Good luck
I live in middle GA. My home is only 8 years old. I have begun to spot leak spots on ceiling in almost everyroom. Condensation forms terribly in the cold months, natuarally leaking down onto ceilings. Also, I am concerned that I do not have adquate ventaliation or any barrier of any type to prevent any of this. My roof is a V design. The center of the home has 16 foot cathedral ceiling and remaining other sections of house have attic space from 8 ft to the 16 ft part. I believe the ridge cap allows in rain as well as all vent areas. What is the best way and also econimcal to correct before serious damage. The house size is 28 x 80. I have 10 ft porches on 3 sides where I am noticing water spots on the plywood at top. Would appreciate any advice. Thanks for your assistance.
Ithink I understand the layout of your rof however I will need aliitle more information to offer an opinion
1) What type of roof material?
2) Describe the roof assembly. Does it have plywood, underlayment etc?
3) What do you have for insulation?
4) What are your interior finishes? Drywall, wood etc.
5) What is the slope of the roof?
6) Describe the ventilation.
7) Are the porches enclosed or open air?
I have been reading these compents about condensation on metal roofs. Seem that most of them talk about ventilation. Just for your info I just installed a metal roof with a vapor barrier. I did not even have the walls up yet, and the whole ceiling was dripping. It was about 18 or 19 degree outside and when the sun came out the whole area started dripping> I even had condensation on the moisture barrier. So I am not sure that the proper vent. has much to do with condensation. PS I am interested in a way to try and stop this problem before I go with a finish. I am thinking I need to pull the metal roof off and go back to a standard roof.
All sloped roofs require vetilation.
All roofing products condensate to the underside.

You should not use a vapour barrier under a roof only a moisture barrier that breathes and traps moisture. typically felt paper is used.

It also sounds like you are under construction and that you did not use wood sheathing under the metal. You have a lot of moist air hitting the underside of the deck and when the sun comes out it will condensate.

When construction is completed, the attic vented properly and an air barrier installed under the interior finish, then the attic will vent and dry out as you have eliminated the moisture source.

If you installed a vapour barrier under the metal roof such as Visquene, then you have a problem and need to remove it.
Well, folks, I am down in southwest Mississippi. I have a vaulted ceiling, solid vinyl decorative soffit showing on the interior, sandwiched between 6 x 12 exposed rafters on 6' centers, above which is 6 inches of foil backed foam panel also sandwiched between the rafters, above which is 2 x 8 lath strips on 24 inch centers, and to that, painted galvanized steel roofing is screwed to the lath in the flats. It is on a 6/12 pitch, and the panels are 38 feet long, extending over a 10 foot wide porch with 24 inch overhang, front and back. This roof will be 5 years old on new house construction, and has sweated and leaked from the getgo. It is the next closest thing to being in the Rainforest Cafe. This roof was not installed over sheathing, nor does it have a vapor barrier, or membrane. I am going to have to pull this entire roof off, go back with sheathing, and a membrane layer, and re install the roof. Condensation runs down the rafters, and some rain gets in either through screws with the washers rung off, installed too crooked, or enlarged holes by letting the screw get away from them during installation.
The installers installed it as recommended(obviously by some idiot). I am no expert, but I can tell anybody considering a metal roof, the presence of barrier substrates (and ventilation if necessitated by the structural design of the attic ceiling) and quality of installation is the whole game. A roofer can find and fix screwhole leaks, but he can't do squat about the condensation getting into your house. Its re-roof time.
I am going to have to have this roof taken off and reinstalled, all 5200 square feet of it, and I am not happy.
If you live in an area with no rain, no snow, no cold, and no humidity, you can install a metal roof just about any way you want to. However, for the rest of us, there is conflicting information about installation of these types of roofs, and this is where the problem lies. There are hundreds of contractors installing these roofs that do not have a clue about preventing leaks and condensation through necessary and appropriate installation. If you want to do it right, this is the way I figure it needs to be done.
Rafters, 5/8 inch plywood sheathing, barrier sheeting such as rain guard, which is sandwiched polycarbonate roll material with a semiviscuous center that is both waterproof, and seals around the screws(not cheap), lath, and roofing, or, in my case rafters, lath, plywood, barrier sheeting, and roof. I am going to reuse the same metal, sealing the enlarged holes, and going back with 4,500 new screws at twelve cents a pop. I estimate this repair to be somewhere around ten grand, using the same roof metal, all because of somebody's lack of installation knowledge.
The plywood and barrier sheeting should provide adequate temperature buffer to reduce sweating, and any screwups in installation allowing water under the roof will be countered by the sealing roll barrier, and any leaks will run off at the eave. Tom, Todd, Dick, or Allan, do you have any problem with what I have said? By the way, surfing the internet trying to get a concise answer as to how to install metal roofs is hopeless. Actually, the only profiles I was able to find were those illustrated by the roll barrier people, like rainguard, and some of the others. The metal roof manufacturers are very vague, with little or no information on the internet, and seem to be hung up on ambiguous answers because they just dont know the design of YOUR house. What a crock. The fact that you have so many questions from so many people on this website points up just exactly what I am getting at. If you are contemplating a metal roof, and it doesn't matter what the structural design of your house is, you absolutely must have an adequate temperature barrier between inside temp and roof temp, such as insulation, and plywood or OSB sheathing, plus a laminated moisture barrier, and lath. You shouldnt have any problems with leaks or condensation, and to me, that looks like the bottom line. Email me with your comments and/or opinion. Thanks, Ed
We hate to hear about the projects that go sideways and you are right in that there are a lot of vertical rib metal roofers moving over to residential with panels and installation details not approved. Our MRA member manufacturers subscribe to the Minimum Performance Guidlines for Residential Metal Roofing published by the Metal Construction Association. Our firm has a very detailed set on installation instructions for our products and our products carry a number of product approvals which is a good mark to look for with any roofing product.

Before I removed it I would try couple of things. First I would install vented closure strips at the ridge and eaves to allow for some air movement. If you want more then vent the eaves only and put a power vent at the ridge to vacumn uniformly across the ridge but use it only when it is not raining or you could siphon the rain in.

There are three sources of moisture, condensation, heat loss and leaks. With SIPS panels in your area you should not have a tremendous heat loss however check around your kitchen and bathroom stacks etc.

Your sheets are quite long at 38' for a through fastened panel and depending on the colour could move up to 1/4" with thermal movement. This is 1/8" at each end of the sheet provided the screws are not overtightened allowing for the movement. Again this is worse case.

Yes you can overtighten the screws and which will deform the rubber washer and direct water in. I would contact one of the major screw suppliers such as Atlas Bolt and Screw and select a new srcew that is larger in size both in shaft gage and washer. They have some excellant screws with aluminum shielded rubber washers.

I would try to identify the metal maufacturer and ensure that you have a roofing profile and not a siding profile which will need a sealing tape in the laps if used as on a roof.

If you stop the leaks then you stop the water and you can dry the air space out.



Our current asphalt shingle roof is leaking and we are about to re-roof. Reason of leaks in low sloping roof and previous owner failed to do some things properly. We are considering replacing with a tin roof thinking it would prevent leaks better. Oon a low sloping roof how well do tin roofs function in keeping rain out. We live in a warm environment -NC coast (no snow) but do get very heavy rains at times.
Most horizontally-run metal roofing styles (shingle, shake, tile profiles, etc.) require a 3:12 or 4:12 pitch. This means that, for every 12' the roof goes back horizontally, it must rise at least 3' or 4' vertically.

Most vertical seam metal roofs require a 3:12 or sometimes a 2:12 pitch. To go lower than that requires a special type of metal roofing intended for low slopes, such as what is used on industrial buildings. Most of these products are "field-seamed," meaning that their seams are formed after installation.

No roofing product should ever be used by a pitch less than what its manufacturer suggests.
I have a Gerard steel roof installed by Horn Brothers. After about every snow storm it leaks. It isn't condensation. Snow physically blows in under the shingles. The shingles don't fit together air tight. The snow under the shingles will melt and run down the tar paper into roof openings like skylights, vents etc. Horn Brothers nor Gerard will not fix the problem for the last six years. I would never get a steel roof again!
I am concerned that I do not know what things to look for when I contract to have my roof replaced
#1 I live in a log cabin in the woods
#2 The house has cedar shakes about 15 yrs old
#3. Some are in the shade and are gathering moss
#4 Ice buildup in areas that get warm in the daytime
#5 We have insects and critters that roam the woods

What questions to I ask the contractor to make sure I get the job done properly
Thank you for your time
Obviously your cedar roof has failed short of it's expecvted life span and you are now considering a permanant roof. This coulkd be because of lower quality shingles, improper instalation, lack of ventilation etc. As well wood roofs need to breathe to survuve and like the steeper sloped roofs.

You should interview the contractor on his experiences, describe your concerns, get his recommendations and a bove all ask for referances on similar type roofs and check them out.

Make sure he identifies the reason for the failing of the wood shingles and steps that he will take to correct the problem. Choose a metal roof system carefully. Some look the same but the metal substrate has differant thicknesses of protective coating. Make sure it is at least a G90 Galvanized if painted and an AZ50 if it is natural. Then itendify the type of coating. Make sure it is a PVDF or a SMP system if painted or a granular coated system.

Once he recommends a system, don't be afraid to contact the manufacturer and make sure it will do what the contractor says. Our fellow MRA member manufacturers agree to supply product that meets the Metal Construction Associations minimum performance guidelines, so choosing one of our members products is a good first step. Good Luck
I too join many of you in your frustration to solve leaks in my metal roof around the flashings. Each and every winter since I had the roof installed the snow turns to ice then the ice slides off, crushing everything in sight, including all the flashings. This results in massive leaks inside and has ruined the ceiling each and every time. This has become very costly, particularly when it crushes my $4 per inch woodburning stove stainless insulated chimney. I'm at my wits end and are considering having the whole thing torn off. In addition, the ice actually peels back the metal roofing in the lower part of the valley (try explaining this one to your ins. agent). Snow guards are not the answer I want to hear because much of the roof is a modified hip and I would have to install a million guards to do the job right. Anyway,I put on the metal roof to decrease weight and I like the attractive style.
My own thought on the flashing protection is to fabricate a FIN that mounts above the flashing, maybe a foot or so high and flaring out downwards towards the flashing so that when the ice lets go, it will be forced to split and go around the openings. I have no ideas on how to stop the tearing of the metal in the valleys. What do you think? HELP!
Jim,

Yours is a pretty complex situation and, really, it's not something I have run into before. I would say that this situation is the result of an exact set of (all the wrong) variables existing in terms of roof egometry, location, etc.

Yes, "witches hats" can be installed as splitters above penetrations. As for the valley situation, perhaps a wider valley or a heavier metal valley would be helpful.

I would like for you to call me at my office at 1-800-543-8938 ext 201 for further discussion. I will try to help you or give you some good resources.

Todd Miller
Am planning an ag building with bi-rib or classic metal roof of 4/12 pitch. Is it recommended to seal the joints at the side of each roof panel? Have experienced leaks after a few years with similar roofs without sealant, don't want to repeat that problem. Are screws or nails preferred?
Neoprene gasketed cap screws are preferred fasteners.

Most products would not require sidelap sealant. However, please obtain specific instructions form the roofing manufacturer and follow them exactly.

Side leaks can sometimes be caused by roof planes which are not level.
Hi Ed, I am having problems getting straight answers myself. I just purchased all the metal, screws, etc, etc, to put a metal roof on my small house in Mass.
I am going over my old roof using the ferring strips, hopefully I won't have problems doing this. My brother is going to be helping me on Sunday (8-10-03). What is the flashing procedure on a stone faced chimney? Help! THanks so much for a reply. Corinne
There are a couple of different ways to do this. I believe I have a message from you at my office. Sorry I have been out of town. I will try to call you tomorrow so we can discuss in detail.

Todd
I am currently building a cottage and I wish to install a metal roof. The temperature in the winter months can drop as low as -35. For this reason I am concerned about condensation.Do I have to sheath over my roof truss or can I strap them out? Would it be better to insulate my ceiling the traditional way or keep the insulation as close to the metal as possible? Do I place felt directly under the metal? Residential roofing is new to this area and I have had trouble getting good advice on correct installation.Thank-you for your help!
In thinking about this, you need to first determine when, if ever, condensation might form in the cottage. Condensation, as you know, forms when warm moist air hits a cool surface.

In the case of an unheated cottage, provided there are no sources of excessive moisture, condensation may never occur. However, if you throw in heated areas or even a damp basement or crawlspace, you could have troubles.

Next, you mention installing over decking or over strapping. The answer for this is based upon what type of metal roof you choose and how its manufacturer says it should be installed. Do not use any other determining factors. The same goes for the underlayment choice.

The way to avoid condensation is to have a well vented attic space beneath the decking or the strapping (whichever the case may be.) Good ventilation requires intake and exhaust. Typically, using soffit vents for intake and a full ridge vent for exhaust works best. Make sure that the metal roof you choose has a suitable detail for ridge vent.

Insulate down on top of the ceilings over the living space.
I had a metal roof put on my house and an awning built over walkway from porch to my husbands building. Both are attatched to house and the walkway is a cement slab just off my front porch. When it rains it leaks where he attatched the awning to the house. how can it be fixed I cannot seem to be able to get a hold of the contractor who put my roof on so i have to do it myself.
Obviously, there are numerous things which could be happening. Ideally, I'd like to see a flashing inserted into the wall and coming out on top of the metal roofing.

If you can email photos to me at tmiller@classicroof.com, I can make some better suggestions.
I recently purchased a home with a custom built standing seam metal roof. I leaks in several places.I hired a roofing expert to investigate the problem. He informed me the roof was not installed properly and needed to be replaced. I can not locate the installer but I know Custom Built manufactured the roof. What should I do?
Custom-Bilt Metals is a member of the MRA. They are based in South El Monte, CA. I think that, if you contact them, they will be very helpful in terms of assessing the situation and making some recommendations.
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