I’m shopping around for suggestions on the hands-down best paintable caulk for my new fiber-cement siding job at both the plank butt joints and the plank/trim intersections. Price is a lesser consideration than durability and latex paint holding ability. This is Chicago, so the temperature and humidity extremes are pertty substantial.
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Stampede - polyurethane caulk. Sherwin Williams. Puuuuuuuuuuuurfect for Hardie. It'll probably only last 35-40 years in your climate though.
"If you pick up a starving dog and make him prosperous, he will not bite you. This is the principal difference between a dog and a man." - Mark Twain
lexel...put it on everything 'cept your sammiches
Spheramid Enterprises Architectural Woodworks
Tommy, can you hear me?
Why look here?
Isn't Lexel a silicone RTV caulk? Can it be painted?
no, and yes.
Spheramid Enterprises Architectural Woodworks
Tommy, can you hear me?
Why look here?
Just a note that you can speed of the cure of polyurethane caulk by misting it with water. Takes forever to harden if it is cold with low humidity.
I did not read all of the threads, but regarding your Lexel question: it is not a silicone products, and it can be painted. They call it a 'synthetic rubber' material.
Sorry, but I have a personal issue with lexel.
I stocked and sold Lexel for many years...and used and liked the stuff.
So much so that when I resided my originally Boise Cascade sided house from 1973 with Rollex vertical aluminum siding in 1987 that Lexel was used at the needed junctions in the system.
Three years ago I did a complete maintenance rework of the exterior and in particular the houses original Andersen Beauty Line all-wood windows and found caulking problems.
The clear Lexel had yellowed, become very brittle and lost adhesion to a large percentage of the contact surfaces. There were water leaks and damages that were repaired and all the remaining lexel caulk lines were cut out and replaced. It averaged about 4 hours per window for the 54 windows in my house. Pluss the other additional siding interfaces.
I vote "No" on the Lexel and "Yes"for the polyurethane....but 20 years down the line, will I again be sorry?
.............Iron Helix
You may have had a bad batch. I recently spoke with a budddy whos house we restored over 20 yrs. ago..all is still fine as far as what was caulked with it.
he is in SE Pa, not "extreme" weathering.
I hope your problems are a fluke.
Who knows what poly will be like in 20 yrs.?
Spheramid Enterprises Architectural Woodworks
Tommy, can you hear me?
Why look here?
Weather flex from dap is very good. Lowes carries it under the weather flex name, the supply houses carry the same product but the name is Sidewinder. I think it was $4 per tube when I bought it last. It, like all caulking that is meant for FC is not latex (water clean up). You'll want a caulking that is permanently flexible with a high life span. The caulking is like regular silicone, very messy if your not a neat person, so you'll learn to be neat quickly.
http://www.dap.com/retail/retail_detail.cfm?catid=1&subcatid=3&prodhdrid=386
http://www.dap.com/techbulletins/00885.pdf
I second the Lexel suggestion, not easy to find in my area but amzingly good stuf.
Re: polyurethane caulkNothing on the tube about painting this stuff; my supplier says I should wait a week, which usuallly isn't very practical. Anybody with experience with paint and poly?
Edited 5/7/2005 9:26 am ET by nikkiwood
I have used polyurethane caulking on my Hardi-plank and painted it the same day - as far as I can tell it just slows down the cure rate. I have also waited a week to paint the caulking - in the long run I can't tell the difference. I did the first wall on my house four years ago and I can't tell the difference between the caulking I painted right away and the stuff I waited on.
Poly is definitely the only way to go. I used some silicone based (ran out of poly) painters caulk around one window and it did fine the first year. In the second year I noticed the paint on the caulking had cracked and in some places it was separating from the wood.
Texer
Depending upon the brand name, it usually takes about a week to "flash", or so has been my expereience with it.
Where you can, it is better to prime first, then caulk, then do your finish coats. Caulks generally adhere better to painted surfaces than bare wood or fiber cement. I know this to be true for siliconized acrylic latex caulk. I don't know about urethane caulks. In commercial applications, urethanes are the ones used for expansion joints in masonry, so they do appear to stick well to those materials.
I have switched to Big Stretch caulk, made by Sashco. It has something like a 500% expansion/contraction factor, so your joints never open up. You have to buy it direct from the manufacturer because of their stupid distribution arangement, but it's worth it.
Have you checked with your local ACE Hardware store? I've been buying Big Stretch from my local ACE for about a year.
Thanks! Good to know.
Have you actually tried to use it on 1/2" gaps? They claim that it will work, but I haven't had the guts to try.................yet. - lol
Dave, I have used Big Stretch on joints up to 1" wide with great success. These were moving joints, so a backer rod/bond breaker was used behind the joint to prevent the dreaded three-sided adhesion. The stuff is like a rubber band when dry, but much more resistant to weathering.Bill
Thanks to all who have replied to my questions. The discussion has helped beyond measure. If anyone's interested I've posted a reply in the Photo Gallery under the thread "Trays & Hardieshingle" with a bit more on this project.
Bill et all:
Not sure if this was stated earlier, but what type of caulks are Big Stretch and Lexcel? Silicone modified latex? Polyurethane? Elasomeric? Etc? Are they water cleanup?
Thanks,Matt
Vulkem...my bro in portland ore. keeps throwing that one out, and I can't seem to get anyone around here that knows what it is...I'm in the Sacto CA area, anyone with ideas? Would love to try it out, although I have recently fallen in love with that miracle tube, Loctite (sp?)....great stuff. BeckRe-Home Solutions Inc.
http://www.sealantsandcoatings.com
they send samples too...
Thanks....I'll check into it. BeckRe-Home Solutions Inc.
Ace carries it..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
personal observations
received special mail offer of BIG Stretch or whatever it is called - like 4 tubes for $20 - $24 - frustrated w/ myself do I challenge them and ask for my money back or just move on false claims and propaganda
and yes I did notice it now is on paint store shelves and I think I noticed is made by the company that makes lexel
white lightning is fine and one I'll use anytime indoors
Dap w/ silicone is the one I'm most satisfied with - if it is a demanding scenario two coats is fine w/ me
just bought a 4 pack of quad as I've heard good things about it
also note I think I've read some not so kind words about Dap on these pages very recently there was a nice thread on caulk used by a production Hardie sider - maybe had a silica sand component to it and even recommended ? by Hardie
Ace carries it..
A thread title like this and that's all you got to say in it?
I wish Vulkem were more easily accessible here.
This is purely a case of alien identity
you know cheap matters often and when some body sees the price of Vulcuum that they'll do something else..
Steel,I also use the Big Stretch. It is widely distributed in the western states. I used to live near their HQ, so it was very easy to get. Still my favorite exterior latex product.Bill
I work for one of the largest and oldest siding companies in the Northwest. Over the years, we have tried numerous different caulking products.
Currently we are using Quad. (We switched back from DAP)
It is easy to use, not too gooie, and paints very well.
Good luck
Just a minor heads-up here about silicone in commercial work: Some companies have strict rules against using silicone products anywhere in their buildings. This is apparently for two reasons: A few rare people are allergic to the stuff, and it can foul up some electronics manufacturing processes.So always double-check before using silicone in commercial work.
" A few rare people are allergic to the stuff, and it can foul up some electronics manufacturing processes."That sounds like an old wives tail. A hint of truth, but basically wrong.
Standard RTV releases acetic acid when it cures. And if used in an enclosed compartment with things like printed circuit boards it can cause corrosion.However, it is too weak to cause any problem except in a very small area.There are neutral cure silicon RTV's that used specifically on electronics.http://www.ellsworth.com/Catalog/DowCorning.pdf&e=10141
Nevertheless, it's written in to many construction contracts, and failing to read the fine print could cost you big time.
Which Dap were you using? And which Quad are you using now? Any reasons for switching? thx
The DAP we were using was "Sidewinder".
The Quad is just their generic, I think.
The reason that we switched was that in several instances, paint was not sticking to the DAP very well.
We are in the NW too and have tried most caulks. We use Quad quite a bit and sometimes we will use Geocel.
>> Price is a lesser consideration than durability and latex paint holding ability. <<
There is another important factor. Workability. Personally, I find polyurethane caulk the hardest of all caulk to work with. Some may remember I asked about this several months ago. What I learned that it is nearly impossible to work with when temperatures are low and do a neat job - even though it says on the tube it is OK to apply in low temperatures. Heating the tubes helps though. Even when it's warm outside, It's difficult at best and I reserve it's use for special locations where weather resistance is the most critical, like for door installs, and around windows. I gave some to the painters I use, and even at the free price, they would not use it. Maybe there is a brand that flows better and is more workable than others, but as far as I'm concerned, what good is a durable/paintable caulk if it ends up looking like crap?
So, my advice is get a tube or 2 of whatever you select and go for a "test ride" before you buy by the case.
was reading an article in JLC last month april , they recommended a caulk by the name of White Lightning products 800-241-5295 ,http://www.wlcaulk.com a 100% acrylic caulk with a 40 year warranty . FWIW
We tried that 10 years ago and had to recaulk everything with Geocel. I was in high school then and that was my job :-) That Geocel was so good that when we pulled the LP off one house to reside it, we had to cut the caulking.
I've been reading this thread and learning a lot. Good discussion and ideas.
And it amazes me that there has not been one single "Caulk" joke.
Who Dares Wins!
No, those are saved for the thread about sealing vertical butt cracks.
Edited 5/8/2005 10:48 pm ET by DanH
Man these guys ruin al the serious threads.
Who Dares Wins!
Best caulk hands down
At the risk of sounding like a plant from Sherwin Williams, let me say a few things about Stampede. We install windows and doors for one of America's best, large builders. Unlike most builders, their aim is to do things right, the first time, and not to skimp on materials. Yes, i know, that's really going against the typical builder mentality. This builder works in cold northern climates and in hot southern climates. They insist on Stampede. They have us caulk all their windows and doors with it. (Two tubes per window on average) and they have the siding people caulk the Hardy plank as well. We install about 30,000 windows a year with the stuff. And about 1000 doors. Here's how I know it's really good. Once in a while we have to go back and take out a window or door frame. To put it mildly, it's a b*tch. We have to cut the caulk and even then, it pulls the sheathing apart before it gives up its seal. It's so aggresive when it comes to adhesion that you can't get the stuff off you once it dries. You just have to wait for the skin beneath it to flake off. I'm thinking of buying a boat that will need some repair. The first thing I'll buy to keep it water tight and weather proof is Stampede. Find me someone who has ever used the stuff and doesn't think it's the best caulk out there, and I'll buy you a tube of whatever you like better.
adhesion shmesion
Just because a caulk has good adhesion, doesn't make it the "best caulk". 2 part epoxy from West Marine has good adhesion, but I wouldn't caulk with it.
BTW, If a "best" builder is using 2 tubes of caulk per window installation, then I'd question what he is "best" at.