Home Construction Improvement
It forms a strong yet flexible, crack resistant base coat that is intended for use on the exterior, above-grade portion of ICF foundation walls. B1G Brush It Grey BIG is a dry mix cement parge specifically designed to enhance the appearance of cast-in-place concrete walls. A common practice in residential basement foundation wall construction is to provide a cement-based parge coating and a brush- or spray-applied bituminous coating on the below-ground portions of the wall. This treatment is usually required by code for basement walls of masonry or concrete construction; however, in concrete construction, the.
By Todd Fratzel on BasementsInsulation. So we thought it might be a good idea to clear up some of the confusion. First off you need to think of your concrete or block walls as a huge sponge for moisture water vapor. The adjacent sketch shows an unfinished, un-insulated, un-heated basement wall.
The point here though is how moisture in the form of water vapor leaves the foundation walls and migrates into the basement space or outside above grade. I'm full time builder for a large construction company in New Hampshire. I run their design-build division that specializes in custom homes, commercial design-build projects and sub-divisions.
I'm also a licensed civil and structural engineer with extensive experience foundatiln civil and structural design and home construction. My hope is that I can share my experience in the home construction, home improvement and home renovation profession with other builders and home owners.
Please feel free to contact me if you have any questions, suggestions or you'd like to inquire about advertising on this site. All posts by Todd ». Search for more articles here. Enter keywords like, 'insulation' or 'kitchens' etc to find your topic. I was interested in following your article above on how to insulate the basement and vapor barriers, etc. I noticed how you bow frame infront of the foam and to leave a one inch space between for air flow.
How do i help to keep the foam attached to the wall?? I was going to use an adhesive and then frame up against to keep it fojndation place, but the air space you said was better. Also, my township requires horizontal and vertical fireblocking. How do i incorporate this into your instructions and diagram above and still be in code?? Note: i am not covering or finishing my ceiling. Rob — We typically use an adhesive specifically made for foam board.
The key is to put the adhesive on the foam and let it sit for a few mins before you apply to the wall. That allows a skim to form on the glue and it sticks better to the wall. Good luck. My township website shows a diagram of the fire blocking on a finished basement wall, and uses horizontal and vertical blocking. Rob — What foam product are you using? Rob — You have it correct. The product you are using is probably the top of what coal for multi fuel stove line…but certainly will do the job!
Any reason not to?. Ceiling is insulated with plastic covered foubdation and will be covered with drywall. Walls have been uncovered for 15 years so they are as dry as they will be. We use a de-humidifer ithe room. Most of wall area is completely below grade. Also if I can use this set up, do I need a platic vapor foundarion under paneling? What type of formaldehyde free foamboard do you redommend? Thanks for your advice. Gary — I would glue the foam board directly to the concrete.
Then place your furring over the foam and secure it through the foam into the concrete. Either that if frame a wall in front of the foam. Be sure to tape the seams well. No need for a vapor barrier.
Good luck! It shows how I recommend you insulate the basement walls. Reading your article has made me re-think my approach to insulating my basement walls. I live in Upstate NY, where the Winters are brutally cold. My 5-year old house has how to parge icf foundation basement walls. I intended to fill it with R fiberglass insulation. One question, however. I am not sure if I should use a faced insulation or not. Any suggestions? Todd M — Thanks for visiting the site.
Hello Todd, I am having my basement redone now a fire. The basement was previously finished with chip board paneling partially over framing and partially directly on the concrete. We will be using dry wall. The basement has never had moisture on any of the walls, but it is always colder in the winter and summer then the rest of the house. Is my contractor correct, or should I insist on insulation on the outside walls of the basement?
Greg M — First off it partially depends on where you live. However, I would insulate it regardless if it were my home.
Todd great article, just ordered my rigid foam and materials to frame the basement out. I live in Northwestern Indiana and will be finishing my basement as to your article. As an extra form of protection we used Epoxy on all the joints and used Zinsser waterproofing paint LX. Also for the pink foam which side goes towards the concrete? Lastly we have had a moisture problem on the Rim Joists where air seems to be getting trapped between the Batt Insulation and the Rim Joist creating dampness.
Would this work well for the Rim Joist? We are looking for the best solution before we get to the drywall portion of the job. Happy New Year! Apply it to the foam, let it stand for 5 mins what is the gaelic word for grandmother it fiundation over then apply to the wall.
Foam board works great on rim joists. My plan is to use the encapsulate fiberglass insulation. I prefer working with it. Is there a problem in using totally encapsulated fiberglass? Best of luck. I have read all of now articles on foam board and vapor movement, but do not understand how the foam board approach solves the problem of trapped vapor. If the foam board is glued tightly to the wall avoiding the air hiwthe water vapor still needs to go somewhere. Why would it not just penetrate the foam board and cause the same problem as insulation?
It seems to me that the foam board is as much of a vapor barrier as foil-backed insulation, which everyone agrees is a problem. Can you help clarify? I have a below-grade basement year-old how to tow a car with a pickup truck that is freezing cold in the winter, so I am trying to insulate in some way.
I also have some minor seepage that comes through the wall during heavy rains. Paul — Properly installed foam board insulation can create a very effective vapor barrier. Foam board foundahion has the benefit of not promoting mold growth like fiberglass. First of all the foundation walls are FULL of water and we ffoundation to keep that from getting to the framing and wallboard.
Secondly we want to keep any moisture from the finished space from passing through the wall and hitting a cold surface where it could condense into liquid form and saturate the framing and wall finishes.
Closed cell foam insulation products provide a great barrier to vapor movement. I hope parfe how to parge icf foundation. I have 40 year old pored concrete walls that have never had a water problem in turns of seepage, though have scaled off the original paint job considerably in some areas. Should they be repainted before gluing the foam board to them? Also, is a combination of foam board and batt insulation the way to go in insulating the areas above the sill plate?
The idea of using both foam board and fiberglass is a more economical hybrid. I have been searching endlessly and i believe todd explained this finally for me. I have a 4 year old house southern Ontario it has a delta membrane on how to parge icf foundation outside foundation… builder has put up R12 fiberglass batts about ft down on the concrete wall. What is the holding temperature for cold food tape into existing upper half.
Then put dricore down, add metal framing on top. I want to use XPS or EPS directly on the rim joists and seal around with canned spray foam then add roxul insulation pqrge everything. Then no more vapour barrier just drywall it up. I know this is not code, but can you foresee there being problems with this hybrid insulation method?
Secondly, I would remove the existing fiberglass insulation. You need foam from the top to bottom on the walls. Hi Paul I was following your post as I need to insulate my basement block foundation and was thinking of using Durofoam 1.
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The Bituthene System sq. ft. Waterproof Membrane and Conditioner is a flexible, pre-formed membrane designed for foundation walls, tunnels, earth-sheltered structures and more. Jun 29, · Here at GBA, we regularly receive questions from readers about the best way to insulate a basement wall. Since these questions pop up frequently, it’s time to pull together as much information as possible on this topic. In this article, I’ll try to explain everything you always wanted to know about insulating basement walls. Jan 22, · The same tools used for stucco work are used for surface bonding and parge coating of dry stack cinder block. The pool float is a hockey rink shaped applicator preferred by many to work the stucco or SBC into place. A foam handle is nice, if you keep your tools clean. Otherwise, composite handles are much easier to maintain.
Dry stack concrete block cinder block technique uses surface bonding cement SBC instead of mortar for high thermal mass HTM thermic walls that are waterproof and much stronger than conventionally laid mortar block walls. SBC 'stucco' with horse hair and calcium carbonate was used hundreds of years ago to build huge water storage cisterns. So it should be nothing 'new' to an experienced engineer.
SBC is commonly required by local building code for sub-grade mortar block walls to ensure integrity. With dry stack construction, only the first course is bedded in grout on the footer to establish plumb and level for the wall.
The rest of the dry stack block courses are laid without need for any mortar between blocks as long as they are of uniform size. Should you have poor quality block in your area, a thin coat of mortar can be added wherever needed to bring wall back to plumb. No need for importing expensive special 'interlocking dry stack blocks' when you are dry stacking with SBC. Locally sourced common concrete or cinder blocks are fine.
Dry stack block with SBC was never the primary focus of our HTM design, simply an economical construction option for homeowner-builders. Other thermic wall building materials are functionally as effective: concrete, rammed earth, adobe, superadobe, and slag, stone, or bag walls. SBC is featured here given its ease of construction and better acceptance among engineers, building officials, mortgage brokers, and insurance companies.
Engineering can be identical to mortar block walls common to commercial buildings, with SBC adding waterproofing and a great deal of torsional strength. Blocks for dry stacking with surface bonding cement do not need to be of any special design. They don't have to interlock, and best of all you don't have to know how to lay block. You simply stack the concrete blocks in a running bond pattern and then parge coat both sides with a single layer of fiber reinforced, surface bonding cement.
Once your block walls have been surface bonded, hollow vertical cores minimum every four foot and alongside every opening are filled with ready-mix concrete grout and a 5 rebar for an exceptionally strong heat storage mass. While possible in theory to rely upon SBC for flexural strength in excess of standard mortared cinder block wall construction, it is rare to see an engineer pursue that opportunity for a client and scale back rebar reinforcement. SBC is much easier for unskilled homeowner builders without any experience laying block and can make excellent use of large volunteer work crews for a 'barn raising' to speed construction.
Solid, poured in place, concrete walls are every bit as effective, but forming and pouring is outside the skill level of most people. Hiring contractors to build the forms, pour the walls and then return to strip the forms, is always an option when you have money in the budget.
Empty cores in your block walls those not having structural rebar should be filled with cement grout, sand, or compacted soil for extra thermal mass. There is no advantage to having empty cores in the block walls and absolutely no advantage to filling them with insulation. The more thermal mass in a home, the better. Most clients simply order more concrete grout and fill the empty cores while they fill the structural cores, but some clients opt for using sand or dirt excavated from the job site.
The only caveat to using soil to fill the empty block cores is to compact well and cap the top of the core with SBC or mortar to prevent moisture from penetrating.
One key to thermal performance and indoor air quality is to waterproof walls to guard against moisture transference and surface bonding cement was originally designed to line water cistern tanks.
You need to prevent water from traveling through the home's walls, sucking away energy and presenting possible indoor air quality problems. The same applies to poured-in-place concrete walls: the wall needs to be waterproofed on both sides to prevent water transfer. Several coats of low VOC non-porous latex paint is a good solution for waterproofing the interior of a concrete wall. Water and waste lines are best run through stick-frame partition 'wet walls' in floorplan layout.
But plumbing and electrical can be run through the block wall cores, if need be. Wiring in concrete block or poured-in-place concrete walls involves running conduit pipe down through the cores or forms before the pour and then pulling wire later to all outlet and switch boxes. A visually pleasing and labor-saving ways to run some wiring is shown here with half-round logs routered out along the back and holes cut for outlet and switch boxes. Nice design touch that does not require that much carpentry skill.
This is counter to what you are trying to achieve. The empty cores should be filled with concrete, sand or some other solid thermal mass material. These tools are relatively inexpensive from companies like Harbor Freight Tools. Removing air pockets from structural concrete filled cores is very important for ultimate wall strength. You can do a finish coat of stucco to attain a particular texture, though, or use a synthetic stucco mixture. Water absorption and transference must be stopped to maintain interior air quality.
A high quality non-porous latex does wonders. Reinforce with galvanized chicken wire or expanded lathe for structural integrity. If you are not familiar with laying block mortared or surface bonded , after the corners are stacked six to eight rows high, setting the string line is critical.
The corners dictate the walls between. Starting from corners, you simply stack block between. You can alternate last blocks, but it is generally the center block and it rarely needs shaved to fit.
There are probably as many different ways to knot the line block as there are masons. Xing at the knuckle full corner end of wooden line block certainly helps stabilize or you can just wrap the string once or twice around block lengthwise, then anchor back to pin. You can pull in slack a lot easier this way, cinching to line pin, plus it ensures the string line will remain taut and true. While it is possible to simply set the wood line block on corner and tie off with tension alone, having an anchor post pin as shown is a little more elegant and saves the string from being subject to jumping off.
As with almost everything in life, there are at least two opinions on the correct usage of the string line mason line. This allows you to use your fingers as a quick spacer - as soon as fingers touch line, you know you are about true for stacking.
You can't always be looking down on the block, though, and you really don't need to with dry stack. Some masons like the string line right where the blocks are going. Nothing should ever touch the string line or it is compromised. It is possible to keep the wall plumb vertical and level horizontal without a string line reference, but the only way to keep it straight true is with a string line. The beauty of dry stack SBC versus mortar block is not having to make sure each and every block is plumb, level and true before setting the next block.
When you are rolling along with stacking the block, you never stop to check every single block A large rubber mallet does a quick and efficient job of trueing the wall until you get two or three courses atop the errant block. This is where you notice the great strength provided by friction with six blocks touching the one you want to move and gravity at play.
After the surface bonding cement is applied and structural cores filled, a SBC block wall is actually much stronger than a comparable mortared block wall A major time saver is never cut any blocks for the layout so you should design around using all full and half blocks.
Block layout we normally work with is eight inch wide block 8" wide, When the design requires changing to 12 inch wide block berming into a hillside you suddenly need to cut a block every other course.
The first course is traditionally all full blocks 12 inch by Half blocks are used at the end of a wall or doorway opening, not in a corner or on a straight wall run between two corners. Any cement based product needs to cure slow and steady for optimal full-strength and that can take up to a month for a concrete slab. If you want a quality product, get several hand pump sprayers for misting water during construction.
Tent and heat the first course with mortar bed and keep it moist for the first few days of set, especially when temperatures are going to dip below 50 degrees.
The same applies to any SBC work later. When dry stacking or mortar block laying in a cold climate, you should consider covering the entire structure with string reinforced poly sheeting. The tops of block walls can be spanned with a few beams and clear tarp material draped across all walls.
Common roll size is 20' by ', with 40' by ' available in some areas. There is also a woven mat material. Commercial projects often leave the plastic tent in place for the entire construction, cutting away with razor knives after the ceiling has been oiled and interior is ready to work.
Then the clear tarp just falls to the floor and becomes a drop cloth to keep traffic off concrete. Dry stacking is addressed on our website as a courtesy to our HTM clients interested in alternative high thermal mass wall construction techniques and not something we specialize in. Legal liability dictates engineering details are site-specific and dependent upon site and soil conditions, local building code, and the floor, wall, and roof construction methods.
If the manufacturer of surface bonding cement being used is not able to provide construction advice for their product, it is best practice to hire a local structural engineer. Unfortunately, we are not able to provide such services. Surface bonding cement SBC dry stack concrete masonry unit CMU block wall and monolithic foundation details are typical and common to any size building, but will naturally vary depending upon size of structure, soil and site conditions, and local building codes requirements.
Conservative engineering practice is to design SBC wall reinforcement rebar in the same grid pattern as a mortared block wall, given site, soil, and foundation variables. In high thermal mass construction, it is standard practice to fill all cores. No hollow cores in an HTM. Non-structural cores can be filled with sand or similar. But in practice, if you are 'shooting cores' with a pumper truck, it is sensible to just go ahead and pour all cores with concrete 'grout' while you have the machinery on site.
We no longer provide construction, consultation, or engineering services and any information presented on this website is for 'entertainment purposes only'. Site, soil, and local code requirements are only the first of many unknown variables. We do not warrant information for any errors or omissions.
Plans are not presented as construction ready. Local engineering approval must always be obtained first, before building. Click on drawing for printable Adobe. Best wishes for your project. The top row of concrete blocks in a wall is constructed with 'bond beam' blocks.
They come with knockout sections that are removed to allow laying horizontal rebar, as noted in drawing above. Depending upon engineering needs, bond beams can be specified for only the top course, to tie the vertical reinforcement of wall together, or one bond beam may be specified every fourth course when horizontal loads are encountered, as seen in a bermed wall.
Bond beams can be used to construct lintel beams over openings for doorways or windows. These U-shaped masonry units span gaps in walls between two vertical supports and space is filled with cement grout and horizontal rebar reinforcement. This drawing illustrates a mortared block wall, but dry stack with surface bonding cement follows the same design.