Thermal properties of plantbased materials such as straw clay and straw bales 3, 4, flax shives 5, cork 6, rape straw 7, corn stalk 8, cotton 9, jute straw 10, palm wood 11 or. Your insulation layer looks like minequite a bit of clay, which may make it more like another thermal layer. Straw bale construction has many advantages, including the carbon sequestration of the material, low cost, availability, fireresistance, and insulation values. Strawclay or straw bale houses are constructed in one of three different methods. Straw clay insulation test sample preparation three components were mixed to make the straw clay insulation infill for the thermal tests. Part of straw bale houses design and material properties prepared by jorgen munchandersen, birte moller andersen and danish building and urban research. A light coating of clay acts as both a binder and preservative. Strawclay, also called straw slip clay is one low tech, low cost solution. Sustainable earth walls to meet the building regulations. Chopped straw can come any in any bale form, from any grain crop. Straw bale constructionprint version introduction to building with straw bales history while use of grassfamily plant fibers has long been a part of building methods worldwide, dating far back into prehistory, actual strawbale construction was pioneered in nebraska in the united states, in the late 19thearly 20th. It is meant to give clear and straightforward information about how to build houses with bales of straw. Straw and clay, along with high thermal insulation properties, are capable of absorbing moisture from air and donating it back at excessive dryness.
That plaster needs to be pretty strawsawdust heavy to have a decent effect. Light straw clay can be built as a conventionallyframed stud wall with straw clay infill. Pine straw insulation in alternative methods and solutions. If you mix a decent quantity of straw or sawdust into your plaster instead of the sand, things are soon going get warmer in your mud world. It appears that this was the first strawclay house permitted in the state of washington. It can be made into different grades closer to one extreme or the other. Since this is a simple and accessible wall building. Straw clay wall this readilyavailable renewable resource, which consists of highlycompressed bales of hay coated with clay plaster, has been used for centuries in europe and asia. Underlayment materials required to comply with astm d226, d1970, d4869 and d6757 shall bear a label indicating compliance to the standard. Top 8 advantages and challenges of straw bale construction. The straw clay material is a sort of hybrid between pure insulation straw baled or not and pure mass cob for ex. Pdf measurement of the hygrothermal properties of strawclay. The simplest way to do this is to put some water in a bucket and slowly add chunks of clay, squashing, squeezing and mixing with your hands as you go.
Apr 12, 2016 clay can be dry bagged clay or site soil with 2550% clay content. Light clay straw insulation endeavour sustainable building. Insulation materials, particularly where green specification is concerned, divide into socalled natural materials and manmade materials. Nonloadbearing straw bale walls are mainly used for external infill above the dampproof course level in moderate or sheltered environments. The mean thermal conductivity of the actual light straw clay insulation was 0. Their thermal behaviour, equilibrium moisture content and water vapour permeability are assessed in order to determine their suitability as a construction insulation material. Pdf strawclay mixtures are composed of unprocessed earth mixed. Clay houses like all homes have some upfront expense when building.
The total volume of light straw clay insulation is 27. Lsc is a mixture of clean dry straw, soil with 50% clay content, and water, with an estimated insulation value of r2 per inch. The straw is the stalk of the grain without the grain head. Straw bale building has seen a renaissance in recent years. The volume of light straw clay used in walls, floor and roof is listed in table 3. Strawbale construction has many advantages, including the carbon sequestration of the material, low cost, availability, fireresistance, and insulation values. The basic process involves making thin slurry of clay and water and then mixing this with straw. These were wisconsin wheat straw, brown clay from surface excavation near madison wisconsin here after called madison clay and tap water. Straw insulation for the home green building elements 2020. Building from natural materials such as clay or straw is often a contribution to the. Clay houses are nearly invincible to most weather conditions and unphased by chemical attacks. It has a very high insulating value, is also superb for sound.
My understanding now is that you want to mix your straw with a clay slip very runny clay and end up with as much straw as you possibly can just enough clay to hold it together. Straw bale homes cost almost exactly the same amount of money to build as traditional stickframe homes. Straw bale walls must be protected against driving rain by the coating and by deep, overhanging eaves. Finally, casein has been used traditionally in construction, it has been. The pounds per cubic foot pfc that is, the density of the wall increases as more and more subsoil is added to the same amount of straw see chart below. One of the best lowcost insulating materials is claycoated straw or other lightweight plant materials. This combination of thermal mass the clay soil and thermal insulation the fiber is called dynamic insulation because in combination these qualities create very comfortable interior climate and a high level of energy efficiency. First thing you are going to do is make a clay slip which is simply clay mixed with water. Natural insulation regulating heat and cold one of the best lowcost insulating materials is clay coated straw or other lightweight plant materials. Natural insulation regulating heat and cold one of the best lowcost insulating materials is claycoated straw or other lightweight plant materials.
This construction method is commonly used in natural building or brown construction projects. Consisting of straw and clay, the raw materials are locally available throughout most of japan. Pdf sustainable earth walls to meet the building regulations. The ecococon straw panel technology is unique providing both a double frame loadbearing construction element and, at the same time, the main insulation of the building. The hay is treated for resistance to fire, fungus and rodents, and the clay can be applied in various densities and thicknesses to ensure the correct ratio of. The steadystate airtoair thermal transmittance, or u value, and the timedependent thermal properties of some proposed sustainable earth wall. Drywall is such a pain to work with and we want something that will give a similar look to the exterior walls. Thermal properties of plantbased materials such as strawclay and straw bales 3, 4, flax shives 5, cork 6, rape straw 7, corn stalk 8, cotton 9, jute straw 10, palm wood 11 or. It uses materials that are almost always locally available and also offers quality insulative properties. Thermal insulation in buildings prevents the heat loss in winter and resists the heat from out in summer. Jun 22, 2017 light straw clay is one of the most versatile natural wall systems around, combining straw s insulation value with clay s thermal mass and preservative qualities for excellent performance in almost any climate. Ive seen pine straw burn when a spark hit and i dont want it in my house. It is a practical book reflecting the authors personal experience, with tips and wisdom learned from his own pitfalls and.
Light strawclay can be built as a conventionallyframed stud wall with strawclay infill. Airsoundinsulation of clay plastered nonloadbearing sbwall. Clay can be dry bagged clay or site soil with 2550% clay content. Straw bales have a larger thickness than most of the insulating. To build with slip straw you will need an abundant supply of straw, clay and some sort of wood for the structure and form work. When considering how to specify an insulation material in terms of environmental impact, it is often the case that the natural material is the most beneficial in terms of environmental attributes.
If youre interested in calculating and comparing the specific costs of building a straw bale home vs a stick frame home, feel free to contact me. These benefits alone make clay homes a sound investment. As already mentioned, house walls were made from a mixture of clay and straw. The heat transfer coefficient for a cross section of the insulated wall was. For the best straw insulation mix i used the same clay mix as before, but this time i made it a lot wetter. The heat insulation value of straw bales depends not so much on the density as expected initially. Apr 14, 2018 the strawclay insulation filled a 12 thick split stud cavity in a single family structure at the port townsend ecovillage. Modeling of temperature regimes of energy efficiency house.
Less wood for the frame replacing stick frame walls with bales can cut by half the amount of timber needed in a modern home, reducing demand on forest resources. Light straw clay is a mixture of straw and clay used as an infill in wood framed construction to create nonload bearing walls. Heat insulation performance of straw bales and straw bale walls. Strawbale construction is a building method that commonly uses straw from wheat, rice, rye and oats, as building insulation. Comparing with straw bales the strawclay blocks provide higher fire resistance and smaller deformations. It is spreading fast like a wildfire to every corner of the earth. Straw bale is very suitable as infill insulation for timber frame buildings with. I can vouch for the longevity of the finished product. Download this article in pdf format e3s web of conferences. Building your straw bale home is a howto book for people interested in straw bale building. Straw bale construction is a relatively sustainable construction method, with straw being a renewable material that is readily available. The place was built by german immigrants probably about 1870.
Straw bales may be used in both infill nonloadbearing and modest loadbearing wall applications. Characterization of thermal insulation materials developed. Straw lightly coated with clay particles works as insulation for buldings because, like other insulations, it is primarily. The advantages and appropriate use of light straw clay.
On the basis of experiences and tests, which were con. Straw clay, also called straw slip clay is one low tech, low cost solution. Straw bale walls are thick, which give good insulation and thermal inertia that is a product of phase changes of residual moisture. The potential for light straw clay construction in japan.
Econest natural sustainable building system claystraw. The thermal conductivity and diffusivity of unfired clay bricks, a straw clay mixture and straw bales have been measured using a thermal probe technique, with an iterative method for data analysis. Construction of the lock, wattle and daub and the insulating material in. Clay houses resilient fireproof unique and attractive. There are special framing techniques to maximize the insulation value of the wall while reducing the amount of wood required. Characterization of thermal insulation materials developed with crop wastes and natural binders mariana palumbo 1. Straw bale construction is a building method that commonly uses straw from wheat, rice, rye and oats, as building insulation. It is looked to use best thermal insulation materials that reduces all types of heat transfer modes like. Strawclay insulation test sample preparation three components were mixed to make the strawclay insulation infill for the thermal tests.
The thermal insulation refers to all isolators systems that reduce the heat transfer. By bailing the straw, a new life is given to the material. There are some challenges with straw bales that, if solved, could further increase their application in. As the clay dries, it binds the straw together in a surprisingly rigid mass. After the edible part of grains have been harvested, their stalks are disposed of by farmers and in many areas, they are burned. If we have any members in europe or elsewhere and you have straw clay insulation, please send us a photograph.
A minimum of wood is used to achieve a construction that is cost effective and with no thermal bridges. Claycoated straw has been shown to last over 700 years as a nondeteriorating insulation. Ill bet yall could poke a bunch of it down inside of your pants legs, if you tied a string around your ankles, and fillem up good, right to the belt. It is a bit heavier than a standard wall with fiberglass insulation and sheetrock, but not terribly so. In about 1978 i helped my dad insulate an old farmhouse near kitchener ontario canada that had straw clay in the attic.
For this mix i would definitely recommend using a sand pit and a garden spade to mix it all in. Straw clay can be used as an insulating infill in any kind of woodframed wall, such as a timber frame or a conventional stud frame. Strawclay insulation and permeable wall system at port. The moisture handling capabilities of straw clay insulation are a key advantage of this material straw clay insulation is only a moderately effective insulator. Mar 09, 2009 low embodied energy unlike manufactured insulation materials, straw is natural and nontoxic, plus it doesnt require much processing and delivery to a building site. Erecting a structural frame allows the builder to put up and cover a roof before even bringing the bales onsite, allowing the walls to be erected under constant protection. Sprayapplied polyurethane foam insulation shall comply with astm c1029, type iii or iv or astm d7425. Research has shown that strawbale construction is a sustainable method for building, from the standpoint of both materials and energy. Airsoundinsulation of clay plastered nonloadbearing sbwall in danish only, direct translation requests to user. It is looked to use best thermal insulation materials that reduces all types of heat transfer modes like conduction, convection and radiation. Which is basically done by mixing in lots of straw into clay. Homes insulated with straw bale can have insulation values of r30 to r35 or more. Insulating a clay oven with a clay and straw insulation mix.
Loadbearing straw bale structuresa summary of testing and experience to date 1. Jun 06, 2019 slip straw is an easy and energy efficient way to build lightweight homes or walls. Light straw clay can be infilled in nearly every wall framing system, be it timber framing, pole framing, conventional lumber framing, or framing specifically designed for straw clay infill. Strawbale construction is a building method that uses bales of straw commonly wheat, rice, rye and oats straw as structural elements, building insulation, or both. I then got a big bag of compressed straw and started mixing it in.
The following information is quoted from an insulation for san pablo. A thread about light strawclay construction straw bale. Thanks to this a favorable microclimate is always in. Thus, for every 1m3 of light straw clay insulation, 1. Straw bale constructionprint version introduction to building with straw bales history while use of grassfamily plant fibers has long been a part of building methods worldwide, dating far back into prehistory, actual strawbale construction was pioneered in. The farmer makes some money by selling the bales and the homebuilder gains an excellent insulation and building material. Underlayment for asphalt shingles, clay and concrete tile, metal roof shingles, mineralsurfaced roll roofing, slate and slatetype shingles, wood shingles, wood shakes and metal roof panels shall conform to the applicable standards listed in this chapter. Straw bale construction is a building method that uses bales of straw commonly wheat, rice, rye and oats straw as structural elements, building insulation, or both.824 1434 1380 221 649 1479 827 1282 449 151 1049 1383 291 346 969 1005 66 1005 1253 1233 192 486 999 354 1418 725 1151 1353 618 207 1239 416 1339 522 194 1288 180 1046 715 68 326 669 1118