To comply with Hardie’s warranty, installation must follow the manual to a T, requiring the use of mount blocks around exterior penetrations such as light fixtures, dryer and furnace vents, and hot air vents. For building penetrations 1½” in diameter or larger, such as hot air vents, hose bibs, and light and electrical outlets, a mounting block should be installed to restore the weather-resistant barrier of the home after cutting a hole for the penetration. Mounting blocks are recommended for all penetrations and remediate any hazardous conditions that will be affected by the planned work.
Exterior mounting blocks are available for walls with vinyl siding or can be made out of 5/4 lumber. For best results, flash all penetrations first and then install specially designed mounting blocks, such as Tamlyn XtremeBlock. A building consent is usually not required to make a penetration up to 300 mm through internal or external components. A good way to detail mounting blocks on an assembly is lap siding, 1×4 furring strips, and 2 inch polyiso exterior insulation.
📹 Mounting Block Details in High Performance Wall Assemblies
It’s all about the details, and this couldn’t be more true when it comes to any and all penetrations in your envelope. Join Matt as he …
What are the studs on an exterior wall?
Studs are vertical load-bearing members used to support elements in walls and partitions. In exterior walls of one- and two-story buildings, studs are at least 2×4 inches, with a 16-inch spacing. In three-story buildings, studs in the bottom story are at least 3×4 or 2×6 inches, and may not exceed 16-inch spacing. They are arranged in multiples at corners and partition intersections for rigid attachment of sheathing, siding, and interior wall finish materials.
Nailing strips or metal clips may be used to back up interior finish at corners. A grademark identifies the species, grade, grading agency, and mill number, allowing the product to be traced to the mill of origin and establishing its structural properties. Most 2×4 dimension lumber is visually graded and marked with an ink stamp at the mill, ensuring the product’s strength for the application.
Are all external walls load-bearing?
Load bearing walls are typically found in exterior walls due to weight causing pressure both downwards and upwards. Some exterior walls may appear in the interior of a house after renovations or additions, but they are still load-bearing. It is important to consult an expert for major structural changes, as most tips can’t be 100% accurate. Solutions Build, a professional builder, can identify load-bearing walls and offer construction services like logicwall, AFS walling, and blockwork. Contact their team for more information.
What is outside wall covering called?
We offer a variety of stylish and modern external wall cladding to enhance your garden. Choose from various colors and textures to create a stunning effect. We also offer porcelain and slate cladding in various finishes. If you don’t have an external wall, you can build one using concrete building blocks and install wall cladding for a polished look. Our Porcelain Rock Stack Cladding is perfect for creating a rustic patio area, as it’s easy to clean and water-resistant.
What blocks are used for external walls?
Concrete blocks are a versatile material used in various external wall construction systems, including solid wall construction, brick and block cavity walls, and two layers of block work with a cavity. They offer high thermal performance and can be used in non-loadbearing situations, such as infill panels in concrete framed structures or internal partition walls. For fire protection, a distinction is made between non-loadbearing and load bearing walls.
Infill panels in frames must consider differential movement of the block work and reinforced concrete structure, as well as lateral resistance to wind. Vertical differential movement can be overcome by soft joints and head details, while lateral resistance can be increased using bed reinforcement. In commercial multi-storey structures with large spans and wind loads, vertically spanning wind posts may become necessary. For more information on specific performance and detailing guidance, refer to BS EN 1996-1-2: 2005 and manufacturers’ information.
What is the outer covering applied to exterior walls?
Plywood sheathing is a type of wood sheathing made from cross-laminated sheets, providing strength and stiffness for expansion and contraction. It is 15-19% lighter and has good moisture resistance. Oriented strand board (OSB) is a durable panel sheathing made from hundreds of thin wood strands hot pressed onto sheets with a wax and resin adhesive. OSB panels are dense and solid, with no soft spots, and do not breath or redistribute water as well as plywood.
OSB is often cheaper but has more volatile pricing. Waferboard sheathing is a manufactured product made by placing small pieces of wood scraps in a hydraulic press and gluing. Although cheaper, waferboard is weaker and less resistant to water.
What is the proper framing for exterior walls?
Framing exterior walls of a home is crucial for their strength and rigidity. Building codes mandate sheathing with plywood or oriented strand board (OSB). Walls in cooler climates use 2×6 framing, while in warmer climates, they use 2×4 framing. The most common wall stud layout is 16 inches on center. Anchor bolts are used to secure exterior walls. Backyard storage shed walls can be framing steps.
What are structural external walls?
This article delves into the concept of external cavity walls and their various materials. External walls serve two primary functions: structural support for floors and roofs, and environmental protection. They must be durable, waterproof, and resistant to weather, as well as thermal insulators. Today, many people prefer soundproofing to reduce noise from outside.
The UK’s preferred wall construction for over 150 years has been masonry, or bricks and mortar. Before the 1920s, houses used solid brickwork, typically two bricks thick, providing structural strength and environmental protection. However, this method did not offer much thermal insulation or noise reduction.
The most significant change in the design of external walls after the 1920s was the implementation of cavity walls. These walls are formed from two leaves of masonry, one 100mm thick brick, separated by an empty void or cavity. The pattern of bricks can determine whether a house has a cavity or solid brickwork external walls. If the bricks are all the same length, a cavity wall is formed, while if they change between long and short lengths, a solid masonry wall is formed.
What do you cover exterior walls with?
In order to conceal a brick wall from view, one may consider the installation of vinyl or wood siding. Alternatively, climbing plants such as ivy or other flora may be employed to create a naturalistic effect. Furthermore, printed brick wall vinyl can be utilised to achieve a bespoke design, while the addition of a trellis with plants or decorative panels can simultaneously enhance the aesthetic appeal and functionality of the property.
What material is used for exterior wall framing?
The most common exterior wall materials used for framing and cladding buildings are wood, concrete, and metal. In 2021, 92 new residential constructions were wood-framed, 7 were concrete-framed, and under 0. 5 were steel-framed. Other less commonly used materials include coffee bean husks, bricks grown from mushrooms, 3-D printed panels, and Earthship walls made from discarded tires.
Framing material is typically covered with final exterior wall finishing materials during the building process, such as vinyl siding. Long-lasting attachments are typically made from metal, but plastic attachments are also popular. These attachments can be in various forms depending on the building’s needs. The main types of siding used in exterior walls include vinyl, wood, and aluminum.
What are the different types of exterior walls?
Exterior walls are made from various materials such as stucco, brick, vinyl siding, wood, stone, and metal, each with its own advantages and disadvantages in terms of durability, weatherproofing, maintenance costs, and energy efficiency. Understanding the specifics of each material is crucial for proper care over time. Regular maintenance is essential to extend the life expectancy of exterior walls.
Inspecting walls regularly for signs of damage, cleaning off debris with a soft brush or cloth, and applying a fresh coat of paint every few years can help protect against wear and tear from the sun and moisture damage from rain or snow.
If extensive damage is found, repairs may be necessary to restore structural integrity and aesthetics. These may involve replacing sections with new panels or blocks, sealing cracks with caulk, repairing holes with patching compound, re-staining wood panels, or repainting certain areas. If you want to completely change the look of your exterior walls, renovations may be necessary, such as replacing siding with stucco or adding stone veneer panels over existing brickwork. These projects should be handled by professional contractors with the right tools and knowledge.
📹 Mounting Blocks // The FINAL Step Before Siding
Here are all the details on the methods we are using to deal with mechanical and electrical penetrations in exterior walls to …
Matt, love your show and learn from your knowledge base all the time, A little tip for you that I used in my remodel. I had a problem with my bathrooms and kitchen vents opening in high winds during NY winter storms and when the outside doors were opened, found a great little trick that worked really well. I glued a small fridge magnet to the inside of the vent flap, then made a 90 deg bend on a 1″ steel washer and glued that to the bottom of the vents pipe. So now when the vent is closed it has some stick value to stay closed but not enough to keep the flap closed when the fans are turned on. Keep up the good work Matt. =)
FWIW: For Vents, hose bib, exterior electrical, I used PVC instead of the hardie board, but used nearly the same technique. Instead of 1×4″ blocking I used 2×10 or 2×12 pressure treated that was primed on all sides, spaced larger than the PVC trim so there is a nail base for the Hardie board siding. It can be a Pain to cut holes in the thick cement fiber board, and the PVC is going to hold up just as well as the cement fiber board. Although I recommend only using the PVC if your using white trim, as Painted PVC is going to crack and peel over time. The with PVC you can also fill the screw holes with pvc plugs to hide them Also I think its a good idea to use the smooth siding instead of the fake wood grain as its less likely to trap dirt and dust. Also the Foam insulation also serves as an additional moisture barrier if its taped. For electrical outlets I recessed the blocks but ended up install covers that would allow me to keep cords plugged in will the enclosure door is closed. This way if I need to keep a cord plugged in its not exposed to rain (ie when you get that fast moving thunderstorm that takes you by surprise). Also recommend using an enclosure with a metal cover since plastic is going to break or crack. Hose Bibs: For garage I recommend a hot & cold hose bib so you have hot water ( ie when you need to hose the mud when its cold outside (perhaps a dog covered in mud ). For cold water bibs, I recommend just using the standard stainless silcocks with a threaded fitting with Drop ear elbows so they are very easy to replace.
OMG, Matt!!! Perfect timing!! I’m right at this phase in my construction and spent this last week planning out the parts to buy. I’ve been planning for Quickflash and Aquor, but was not familiar with the Aquor mounting block. I got some other good ideas here, most notably the Titan outlet. That looks like the perfect solution. You should come visit on your next trip to Boston.
The oil from teak is a deterrent for termites. This is all very cool. I wish they’d had some of this tech back when we were doing some reno on the house decades ago. Wish the Zip system had been around when we had new siding put on. Do you have any tips on products/methods for renovating existing older homes? For instance, I am moving my laundry room (flipping it with an adjacent bathroom) & will need to move the dryer vent. I will need to drill a new hole for the dryer vent (which I believe is 4″), block it out for support, & install a MagVent (have you heard of MagVent?). Since I will be moving the vent, I will have to fill in the old vent but I don’t think I have enough leftover siding from over 15 years ago, so I was thinking of putting some kind of cover over. There will be a bathtub over the hole from the inside. Would spray foam work to fill in the hole? I’m thinking leaving the old ducting (or at least part of it), or maybe just using the round cutout from new duct to fill the hole somewhat. Would zip system flexible tape work to cover the hole from the outside & then put a round piece of plastic over top? House was built in the 40s, 2×4 construction, plywood sheathing on the outside, no insulation inside the exterior walls, some kind of pink house wrap was put under the vinyl siding. We get a LOT of rain here as well as high winds and sometimes hurricanes. Got hit with 2 plus a tropical storm this year. It’s also very humid. Your family’s house looks cool so far!
I hope you do a article showing the installation of that last one, for the AC line sets. One thing I was wondering, looking at that “mounting thing”, was there looked to be a good amount of free air, between where it’s pressing up against the Zip Sheathing, and the “hose/funnel” is routed out through the exterior insulation/siding. I wonder whether you leave that alone, as empty space, or whether you try to fill it up, somehow, say with some foam.
I wish there was a “catalog” of building products. The box stores are full of crap and several times I’ve tried to do internet searches (very time consuming) and eventually found a product for that task… Then AFTER doing the job up pops something that had been around a while, I’d never heard of though and would have better suited but didn’t show up on the search. Recently went through this on a shower mixer valve where looked at all kinds, then too late found one that never showed up anywhere yet would have been my first choice… Too late for the installation. And right now trying to find all sources for basaltic rebar to pick the right ‘stuff’ and wondering what I’m missing. The thing is, there’s a point of diminishing returns on your time, you have to go with what you’ve found and have to stop looking. I don’t have a staff to look stuff up nor do I have time to get every building magazine and notice and read them and even they don’t cover anything but the “latest thing” they are pushing.
Matt, great detail in your build and article quality. Thanks so much for all your work. I know this article is about a remodel so my question doesn’t apply to this project, but it seems like most if not all of these penetrations could be done through the slab with proper pre pour planning? Thanks in advance.
This is awesome! Great article Matt! I’m currently in my BAS degree program for Sustainable Building Science Technology at South Seattle College. I have watched every article you have made and I tell everyone and reference your knowledge and articles to everyone I know and talk to. It would be fantastic if we could arrange to have you on Zoom as a guest speaker? We have had several guest speakers but no one with your experience or in performance home building.
Excellent info,……blocks are the only way to go for a clean, sealed install. A chunk of 2×12 works all the way to the stainless pieces…… The key is the block, whatever material it might be. Lots of customers and builders get scared when they see $1k in fancy mounting block gadgets…….home made mounting blocks from a 40 buck 2×12 get all the function of expensive blocks, just not the same durability/life material wise. Usually for every thing that costs thousands, there is alternative that is functionally the same for hundreds…….or less. A douglas fir home made block will fail the fastest, a treated one will last longer,…….then better and better and better life all the way up to stainless which quality stainless will last the longest. Don`t let the cost of high quality flash/block/trim combos deter you from doing this correctly and just drilling thru the sheeting and siding, then blobing on sealant……..even a lowly treated wood block will give a very long service life for very very cheap.
@Matt Risinger Great info Matt, you definitely got all these details figured out. With all the technology going on there, I feel like the furring strips will be the main weakness of the whole wall assembly on the long term (maybe not in your climate zone though). Any potential alternatives you would recommend?
Matt I love your YouTube website. Thank you for this article detailing good methods to penetrate the walls. I am curious (concerned?) about the foil on your exterior insulation. I get that it would reflect the sun’s heat if it were exposed, but where it will be behind the siding does that benefit diminish? Also, wouldn’t a house enclosed by a layer of metal create a Faraday cage making it difficult to send/receive a mobile phone signal? I’m no house builder so those couple of details are on my mind. Thanks again for your excellent show.
Okay, here’s the thing that I have been trying to figure out for a long time now… I can understand how you want to take time to make sure that a vent penetrating the outside envelope is properly sealed so that you don’t have air leakage into the wall cavity but in the end you still have a large hole directly into your house. For example, in this article you have an 8″ vent hood duct directly to the outside. In a passive house, how is that not a massive air leak? No matter how good a job you do of sealing where the vent penetrates the outside envelope, it’s still a huge opening to the outside!
Cool man you don’t know how bad I wish I ran in to your website years a go when I was remodeling my Double wide. Love all the great new products you show. But now with the price of stuff I have to wait until the price of lumber goes down. But If I new then what I know now I would have been wrapping my home in 4 inch foam ect. To make it supper air tight and warm, or cool depending on what I want my home to be. Man if I ever build a house. I will be following all your great articles.
This article comes at a good time for me. I have really been frustrated with the subs just drilling holes wherever they feel they need to. I think the electrical is the worst by hogging out the siding for plugs and outdoor lights. They do this at trim stage because they’re afraid it will not line up with the siding correctly if they do it before. So I’ve been thinking that won’t matter if there was mounting blocks. I determined my next house (pouring foundation on Monday) will have mounting blocks behind EVERYTHING!!!
A big advantage of insulation exterior of the WRB is that the WRB is protected from heat, extending it’s durability. Joe Lstiburek quotes the “Arrenius” (don’t think I spelled that right) equation which I believe states that lowering a material’s average temperature by 20 degrees doubles it’s lifespan.
Your articles is worth your weight in gold, thank you. I will use your information when i build my home next year. You talk about how important water control is; I was a termite inspector in california for 40 years and the worst damage i ever saw due to water damage. The house was about 5 years old and when i went into the subarea for part of the inspection, it was a rain forest. water was dripping off the insulation and subframing. EVER wood framing was fungus damaged, I was able to pull the the joists and subfloor apart with my hands. To repair it was going to require the entire first floor of the house to be removed, kitchen with granite countertops, marble entryway, build in book cases, etc. and be replaced. It was all due to faulty insulation insulation, they covered all the foundation vents with insulation and this property has a high water table
Great info Matt, I love these product articles as much as the “how to” articles you make! Also, don’t apologize for the long articles, I could easily sit and watch them no matter how long they are! In fact, if you combined all your “Real Rebuild Project” articles together, from start to finish with all the product tips included (like this article), I’d be in heaven! Just saying…
this was a pretty reasonable article. for my part, i did my wall penetrations before applying the exterior insulation. that way, you don’t end up having to cut out insulation as was done in this article. when you are dealing with contractors, that might be difficult to schedule. the other thing is, to do what is shown in this article, you’ve got to want to have exposed mounting blocks. if you don’t want exposed mounting blocks, then the “mounting blocks” that you do use are to provide a nailing surface for your cladding. the use of mounting blocks as shown in this article makes the cladding installation a bit simpler at the penetrations, though.
Two notes about the Hardie pre-painted siding: You can get color matched paint at Sherwin WIlliams paint stores, just tell them the Hardie color you’ll be using and you’ll get a perfect match. Even more useful: OSI Quad Max caulk also comes in colors to mach the Hardie paints. I used those two products and the match was dead on for both of them.
Hey matt, those quickflash panels for the arlington manufacturing recessed boxes wont actually work how youre describing them. They will not seal with any type of mounting block unfortunately, much less a rain screen + mounting block. They seem good in practice but the quickflash things in general have been a no go every time ive tried to use them with a rain screen and mounting block. Youll have to nail through them which defeats the entire point.
Couple of comments: Wouldn’t it be a better practice to locate the exterior utilities prior to installing the exterior insulation? I find it hard to conceive anyone successfully cutting the exterior insulation at numerous locations without damaging the WRB membrane on the Zip sheathing. Would you please further explain the reasoning for the rain screen behind the mounting blocks? I assume it’s because your mounting blocks are Hardie material. In our NE climate zone I’ve utilized different material for mounting blocks. With PVC trim we use PVC for the mounting blocks. This enables us to easily build up the necessary thickness. While I realize you have weather sealed the penetration’s it just makes sense to me for these mounting blocks to be tied into the WRB. The drip flashing in your assembly seems to be limited to siding surface runoff. Maybe I’m old-school, (or just old). I ask as other than Zip R-sheathing, I’ve not had the opportunity to build with exterior insulation, thank you.
I appreciate the material science of these articles, but the layer upon layer upon layer upon layer upon layer upon layer of materials is becoming ridiculous. What’s the market cost of all these high end materials. What is your rough total wall cost per square foot of wall? I can’t see how anyone can afford all of these stacked systems in a single project.
So you have the zip system for a house wrap then exterior insulation. If water vapor is coming inside out and the zip system has some permeability.. won’t that vapor get “stuck” and be unable to diffuse out, rotting the siding materials? Thanks for all the info! Thinking of doing this on my home someday..
Too much talking. Not enough showing. James Hardy: You talk about it all the time, but I have never seen any. Eventually the implied context suggests it is probably siding. Maybe a Texas thing? Eight inch air side vent: You have the guy installing it, but never show the final installation! #10:16 Electrical: It wasn’t clear for quite awhile what the heck this was (vacuum system, air hose, cable or telephone utility inlet?) Then you mention in passing as inserted into blue condom plate. But what is the big picture? What is its final location? #11:51 Hose bib: You show the doohickey, but never show how it gets installed. Does it go through the wall? How much does it penetrate? It may look slick to you, but it does not look functional. #17:49 Why the heck is a manufactured fiber product that is one inch thick called 5/4?
The only person on the planet, other than the people who are paid, that call that siding John Harie, are John Hardie and the people who are paid to call it that. Were you paid by John Hardie to call Hardie Board John Hardie? Most of North America, outside of where you live, actually have weather. Will your systems work in areas that have actual weather, ie. minus 40 degrees? If not, your articles are only useful to people in the southern United States, ie, not the real world.