A to Z of building your own home... X,Y,Z

X-RaysModern architecture and X-ray technology coincide and evolve in parallel. However, the see-through house gained recognition alongside mobile X-ray machines involving programs for the mass X-raying of the entire population. Mobile X-ray machines appeared in places such as department stores, industries, schools, and suburban streets, supported by a barrage of newspaper articles, radio broadcasts, and films. Glass walls, like X-rays, are instruments of control. Just as the X-ray exposes the inside of the body to the public eye, the modern house exposed its interior. That which was previously private was now subject to public examination.For example, in Highlights and Shadows, a 1937 Kodak Research Laboratories film on the virtues of X-rays in disease prevention by the filmmaker-radiographer James Sibley Watson, Jr., a woman wearing a swimming suit is shown strapped to a laboratory table while her body is subjected to X-rays. As her photographic image gives way to the image of her X-rayed body, the narrator declares: "This young lady, to whom henceforth a glass house should hold no terrors, will after an examination of her radio graphs, be reassured that she is indeed physically fit." The glass house acted as a symbol of both the new form of surveillance and of health. Y-ValueY-value is a proxy for the heat loss through the non-repeating thermal bridging areas of a building.  The default value is 0.15. Using Accredited Construction Details in conjunction with the Psi (Ψ) values in Appendix K of SAP 2009 document Part L1A Section 5.12, this can be reduced to 0.08. By thermally modelling the junction details, for most house types, this figure can get down to less than 0.04.Instead of driving down the U-value, say to 0.15 W/m²K or below, using a Y-value of 0.04 can result in a less stringent U-value requirement of above 0.17 W/m²K or possibly higher. This means building with a lower cost fabric without compromising on the SAP value. Or alternatively, staying with the same U-value of 0.15 and significantly reducing the square meter requirement of PVs, or similarly reducing the need for expensive windows or indeed both.For example, in order to move from a Y-value of 0.08 to 0.04, in a detached house, this can result in a reduction in the window U-value requirement by 0.42W/m²K. This is the difference between using double glazing instead of triple glazing. Alternatively, the building fabric U-value requirement could be reduced by 0.09W/m²K. Either that or eliminate 3m² of PVs. ZoningZoning represents the selected legal areas in a municipality, which are controlled by authority in order to permit and prohibit various land uses. United Kingdom's system of town and country planning relies on a discretionary "plan-led system" whereby development plans are formed and the public consulted. Subsequent development requires planning permission, which will be granted or refused with reference to the development plan as a material consideration.In England, zoning is divided into 4 Use Order Classes. Class A covers shops and other retail premises such as banks and restaurants, Class B includes workshops, factories and warehouses, Class C are residential uses and Class D are non-residential institutions, assembly and recreational uses. Each class includes sub classes that define uses in greater specificity.Additionally, zoning may also indicate the size and proportions of land area as well as the form and scale of buildings, which are set in order to conduct urban growth and development. Zoning can also be defined as a technique of landscape planning as a tool of urban planning used by local governments in most developed countries in order to standardize building form and relation of buildings to the street with mixed-uses (form-based) or separating land uses (use-based). Similar urban planning methods have dictated the use of various areas for particular purposes in many cities from ancient times.