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Acronyms, Abbreviations & Glossary Of Common Terms


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#1 joiner

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Posted 13 April 2015 - 08:25 AM

*
POPULAR

ACRONYMS & ABBREVIATIONS

{AAV = Air Admittance Valve. (Sometimes referred to as a Durgo Valve.)
{AAV (alternative) = Automatic Air Vent.

ACH = Air Change [per] Hour

AONB = Area [of] Outstanding Natural Beauty

Article 4 Direction = Removes Permitted Development (PD) rights. (See: http://www.brighton-...cle-4-direction )

ASHP = Air Source Heat Pump (And see also: http://www.planningp...ects/heatpumps/ )

BC / BCO / BI = Building Control / Building Control Officer / Building Inspector (Often prefixed with LA = Local Authority, as in LABCO.)

BR = Building Regulations (Regs)

CIL = Community Infrastructure Levy (= a charge levied by a LA based on the sq.m of a property. Note: self-builds are exempt.)

CO = Conservation Officer. (Now often designated: Heritage Officers. Specialized - although often not particularly qualified - planning officers working in a local authority Conservation/Heritage department. Have the power to over-rule BC where the Regs are concerned if a proposal is considered likely to impact on the "historic character" of a building, whether Listed or not, or in a Conservation Area.)

{Listed Building, see: http://www.planningp...ing_consent.pdf }

{Conservation Area, see: http://www.planningp...ns/conservation }

CU = Consumer Unit

CCU = Cooker Connection Unit

CWS = Cold Water Storage [tank]. (Large plastic tank often in attic.)

CYL Stat = hot water cylinder thermostat for control of DHW temperature.

DeltaT = ΔT (Greek symbol Δ =delta in Greek alphabet) Temperature difference. (In the building context usually referring to the difference in temperature across a wall when discussing the effectiveness of insulation.)

DG = Double Glazing (Sometimes referred to in shorthand as 2g = double glazed; 3g = triple glazed. Also expressed as 'd/g')

DHW = Domestic Hot Water

DNO = Distribution Network Operator (electricity supply)

DPC = Damp Proof Course

DPM = Damp Proof Membrane

EA = Environment Agency

EDPM = Roofing membrane. (EPDM rubber (ethylene propylene diene monomer (M-class) rubber), a type of synthetic rubber,)

EPC = Energy Performance Certificate (See: https://www.gov.uk/b...ce-certificates )

EPS = Expanded Polystyrene Insulation

EWI = External Wall Insulation

F&E = Feed and Expansion tank. (Small plastic tank often found in attic alongside CWS.)

FCU = Fused Connection Unit

FWIW = "for what its worth". (As in: "That's my opinion FWIW.")

FYI = For Your Information. (Now often seen in formal letters since they took the form of emails, and especially in the header of an email forwarded to keep someone "in the loop".)

GSHP - Ground Source Heat Pump

HC or VHC = heat capacity/volumetric heat capacity

ICF= Insulated Concrete Formwork

IGU = Insulated Glazed Unit (industry term for double or triple glazing)

IMHO = "in my honest opinion." (Alternative: "in my humble opinion.")

IIRC = "If I remember correctly."

IWI = Internal Wall Insulation

KISS = Keep It Simple Stupid. (Usually expressed as: "Stick to the KISS principle.")

LA = Local Authority

LBC = Listed Building Consent. (Needed to carry out work on any Listed building, whether domestic or commercial, privately or publicly owned, which is protected by law because of its historic significance, whether by age or architectural importance attested to by English Heritage.) (See also: Listed Building, above.)

LPA = Local Planning Authority

LPG = Liquefied Petroleum Gas

MCB = Miniature Circuit Breaker

MDPE = Medium-density polyethylene also referred to as Alkathene. Pipe used to carry mains water and gas, usually buried underground.

MI = Manufacturers Instructions

MVHR = Mechanical Ventilation [with] Heat Recovery.

NPPF = National Planning Policy Framework

OEM = Original Equipment Manufacturer

OLIVE = Compressible copper ring accompanying threaded plumbing fittings that compresses around the pipe when the fitting is tightened to form a watertight seal. Often reinforced with PTFE tape [see below].

OSB = Orientated strand board

Party wall = An internal wall common to two properties. (Not always a contentious issue, but see: http://www.planningp...on/partywallact )

PDR = Permitted Development Rights. (Sometimes just 'PD'. See: http://www.planningp...ssion/permitted )

PGM room stat = Programmable room thermostat: selects both operating times and temperatures.

PI = Professional Indemnity (Insurance)

PINS = Planning Inspectorate

PME = Protective multiple earthing

PIR = Rigid Polyisocyanurate Insulation

PoE (or POE) = Power over Ethernet. Enables power to be provided to the device (phone or a network camera) using the same cable as that used for network connection.

PRV = Pressure Relief Valve (also = Pressure Reducing Valve.)

PTFE (tape) = (polytetrafluoroethylene) Tape used to seal threads and joints (e.g. around olives in compressions fittings) in plumbing.

PUR = Rigid Polyurethane Insulation

R-value = Thermal resistance [insulation] (the higher the better)

RCD = Residual Current Device

RCBO = Residual Current circuit Breaker with Overcurrent protection

RDF = Refuse Derived Fuel

RTFM = Read The Flipping Manual. (The polite version; the less inhibited version is usually expressed with the 'F' meaning what you think it means.)

SAP = Standard Assessment Procedure (See: https://www.gov.uk/s...sment-procedure ) (See also: https://www.bre.co.u...P-2012_9-92.pdf ) ( https://www.gov.uk/g...t_file_2012.pdf )

SE = Structural Engineer

SEPA = Scottish Environmental Protection Agency

SFCU = Switched Fused Connection Unit

SHC = Specific Heat Capacity (heat is another word for energy, don't confuse with temperature)

SIPs = Structural Insulated Panels

SSSI = Site of Special Scientific Interest

Stat = Thermostat. (Room stat = wall mounted thermostat/central heating control.)

SUDs = SUSTAINABLE URBAN DRAINAGE [system]

SWA = Steel Wire Armoured (cable)

SWMBO = She Who Must Be Obeyed (Attributed to "Rumpole of The [Old] Bailey", who used the phrase when referring to his wife, but actually from Rider Haggard's "She": https://www.youtube....h?v=bS5YmETSVCI )

TBH = "to be honest" (As in: "TBH I don't know.")

TBF= "to be fair" (As in: "TBF to the builder, he hadn't a clue.)

T&E = Twin and Earth (cable)

T&G = Tongue and groove. (Often given in lower-case: t&g.)

T&PV = Temperature & Pressure [relief] Valve

TS = Thermal Store

UFH = Under Floor Heating. (Also expressed as 'Underfloor Heating' but usually still given as UFH.)

U-value = Rate of transfer of heat [insulation] (get it as low as possible, below 0.15 if you can)

UVC = Unvented Cylinder

VCL = Vapour Control Layer

WUFI = "Wärme und Feuchte instationär" - Heat and Moisture transfer analysis

XPS = Extruded Polystyrene Insulation

ZV = Zone valve, motorised or other. (Directs heating medium to wherever needed according to programmed requirements.)



**Storage area for editing purposes.**





LINKS TO DESCRIPTIONS OF COMMONLY USED BUILDING MATERIALS AND COMPONENTS

PU (Glue) = http://www.christine...lyurethane.html





UNITS OF MEASUREMENT

L x W x H = Length times width times height. (But note that when giving dimensions for windows and doors ALWAYS follow the convention of width first, following by the height.)

J = joule (not Joule)

W = watt

h = hour

s= second

k = kilo (thousand)

kW = kilowatt

kWh = kilowatt hour

kWp = kilowatt peak (Solar installations - literally peak output.)

m = metre (not meter)

m2 = square metre (not metre squared)

t = time

T = temperature

°C = Celsius or Centigrade

K = kelvin (not °K or degrees Kelvin)

k or k often means conductivity

R = resistivity

U = 1/R

g = gram

kg = kilogram (the odd SI unit, use it)

J/(kg.K) = J/(kg.K) = J.kg-1.K-1

W/(m2.K) = W/m2.K = W.m-2.K-1

f(x) = function of x. (Common usage in thermal and stress calculations as well as statistics.)

e = Exponent (1+1/1+1/2+1/3+1/4...) how things heat up and cool down, how fast things grow,

π = pi ratio of a circles diameter to its circumference


Check List: Index and Summary

Edited by joiner, 30 March 2016 - 05:56 AM.
Link to index added


#2 joiner

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Posted 13 April 2015 - 10:09 AM

Contributors:

ProDave
Mafaldina
Peak Oak Frames
Alphonsox
DeeJunFan
SteamyTea
Triassic
ConstructionChannel
Warby
PeakOakFrames
NickFromWales
JSHarris
Uncle Tom Cobley
oh, and All

Edited by joiner, 07 December 2015 - 04:05 PM.


#3 SteamyTea

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Posted 13 April 2015 - 11:43 AM

Delta, often a little triangle, means "difference in", so difference in temperature i.e. warmer inside than outside.

A small delta, an upside down g or q thing, is used in mathematics to mean a very small change, popular in calculus. So if you see the triangle followed by a T, over a triangle followed by a t, that is the change in temperature divided by the change in time i.e kelvins per second, a rate of change.

If you see the upside down squiggle followed by a T over a squiggle followed by a t, then it is a differential equation and a new set of rules apply to calculate it. Just allows you to calculate an absolute value from the rate of change.

Decrement is a term I dislike and never heard it once in all the years I have studied this energy malarky. It seems to mean the speed (but should really be velocity) that something happens. So if you forget about U-Values for a minute, and image that a pulse of energy will take a set amount of time to pass though a material, that is known as the "decremental delay". Not a good term as far as I am concerned, I never use it, Thermal Inertia is the proper term.

Grams and Kilograms, and that pesky letter k. The SI (international system of units, and if you stick to them you make life easy all round) only has a few units, the rest are derived from the basic ones.

For some reason it was decided that a gram was too small a unit so they use the kilogram. It possibly stems from the old 'metric' system, CGS, that used the centimetre, gram and second, which had two things different from the SI. This is why things were standardised in 1960 after 12 years of work.

The 'k" problem is context sensitive. So you would not use Kg, which would mean kelvin times grams, or kG (which is a valid unit as that is 1000 gravities). In my dull reading of the social sciences I have come across k,K and k used to mean a variable, a constant or a 'fudge' number. But generally in science it is used to mean 1000 unless it is italic. Temperature when capital.

The heat and temperature thing are tricky to understand at first, but really quite simple.

Heat, or the more modern term, energy, is really just the force needed to move something a distance. So if you have a box of 1 kg rocks and you move them out 1 at a time and only move them a metre, you have used 1 joule of energy (we shall disregard friction, height difference, gravity for now).
Temperature is the effect that energy has on a material, so if you constantly hammer a bit of metal it gets warm. You have changed kinetic (moving) energy to thermal energy (a higher temperature) in the metal.

This is because temperature is a measurement of the average (mean) free path of atoms or molecules movement. The velocity of them if you like. It is very hard to measure each atom to see how fast it is going, but pretty easy to measure a lot of them and take the average.

This is why on a very cold, but sunny, day, your washing starts to 'steam' on the line. On average both the air and the washing (well the water in it) are below the phase change temperature (liquid to gas), but the rays of the sun hit some water molecules just right that they are raised to greater than the phase change temperature, turn to gas, and escape. You don't need sunlight to do this, wind can do it as well. As cold dry air is denser than warm moist air, it descends, this is very pronounced in mountain areas and has kept Scotland warmer than it should be recently (Chinoock or foehn winds). The physics is very simple, P.V/T = C

All that is saying is that pressure times volume divided by temperature is constant (Ah, I used a C for a constant, instead of a k, confusing ain't it) for an 'idea gas'.

An idea gas is one that only has atoms, no molecules and 'behaves' consistently (no phase change) down to Absolute Zero (0K).

So you can see that even lots of tiny atoms will have a mass, and if you move them you need energy, and if they bump into something they slow down and get hotter.

This may sound a bit theoretical, but generally we are talking small temperature difference when dealing with housing, so is not a problem. If you know the material properties, and the energy input, you know the temperature, this can be worked backwards too (algebra, don't you love it).

Radiative losses are different though, that would be a whole different chapter to do with heat loss (and is little understood but greatly abused in my opinion).

Edited by joiner, 11 November 2015 - 06:46 AM.


#4 jsharris

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Posted 13 April 2015 - 06:44 PM

There are a few general rules with units. Those named after people (Watt, Joule, Amp, Coulomb, Kelvin, Celsius etc) are, by convention spaced with a single space after the numeric value, whereas those units not named after an individual are not.

So, for example, one second would be written 1S, but one Watt hour would be written 1 Wh. The convention is also that units named after people are usually capitalised. So 1 degree Kelvin would be expressed as 1 K, one degree Celsius would be 1 C (or 1 deg C). Both are the same incremental temperature difference, by the way.

There are also some archaic terms still in common usage. Sensible heat is often used to describe heat energy (with the units defined by the user, but in SI terms the units would be Joules). "Thermal mass" is a pseudo-scientific term that has no defined meaning, and so is a pointless term. The correct term is heat capacity, or if referring to a material, specific heat capacity. Decrement on it's own means just to reduce by an arbitrary value, but decrement delay is a defined term that relates to the time taken for heat to travel from one side of a surface to the other, and is dependent on two factors, the thermal resistance of the material and the heat capacity of it.

Edited by jsharris, 13 April 2015 - 06:45 PM.


#5 SteamyTea

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Posted 13 April 2015 - 06:56 PM

"dependent on two factors, the thermal resistance of the material and the heat capacity of it."
It is the product of the two.

And has the abbreviation I, but is not named after a person, so is really annoying.

C is used for Specific Heat Capacity, which is usually written as SHC.

If using an unfamiliar term, spell it out. It will help everyone.

Edited by joiner, 14 August 2015 - 12:48 PM.


#6 Alphonsox

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Posted 13 April 2015 - 07:47 PM

View Postjsharris, on 13 April 2015 - 06:44 PM, said:


So, for example, one second would be written 1S, but one Watt hour would be written 1 Wh. The convention is also that units named after people are usually capitalised. So 1 degree Kelvin would be expressed as 1 K, one degree Celsius would be 1 C (or 1 deg C). Both are the same incremental temperature difference

Pedantically one second would be 1s, one Siemens would be 1S (or 1 S)

Edited by Alphonsox, 13 April 2015 - 07:54 PM.


#7 SteamyTea

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Posted 15 April 2015 - 06:10 AM

If you want to work out how fast your house heat up, or cools down, it is expressed as a ratio, kelvin per second (or minutes or hours).
So...

K/s

This would be worked out by taking the initial temperature T0 from the final temperature T1 to give you the temperature difference ΔT.
The same is done with time, so t1 - t0 gives you Δt
So...

(T1 - T0) / (t1 - t0)

Therefore the rate of change is ΔT/Δt which is just an ordinary fraction or an improper (vulgar) fraction i.e. 10 K / 3600s

But if you see this written as δT / δt you are into calculus and a new set of rules apply for calculations. δT / δt is usually followed by the equals sign and then a formula, something like δT / δt = e(-kt)

Where...

e = exponent
k = constant

This would allow you to work out the temperature at any time in the past or future, ΔT/Δt only shows you what has happened over the test and cannot be extrapolated.

It is quite acceptable to use D to equal Δ and d to equal δ, but it is not usual to use Delta or delta to distinguish between a fraction and a differential equation.

Edited by joiner, 15 April 2015 - 08:06 AM.


#8 Nickfromwales

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Posted 30 May 2015 - 03:01 PM

Just a notice to let everyone know that when they post here it'll have the useful content cut and pasted into the appropriate list, and then the post that brought it here will get deleted ( so this remains a reference point not a discussion thread ).
It gets 'dusted off' regularly by the local sheriff aka Joiner :)
Regards, Nick.



#9 djh99

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Posted 14 August 2015 - 12:05 PM

RTFM = Read The Flipping Manual. (The polite version)

The correct polite version is Read The Fine Manual

Edited by joiner, 11 November 2015 - 06:46 AM.


#10 djh99

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Posted 14 August 2015 - 12:09 PM

View Postjsharris, on 13 April 2015 - 06:44 PM, said:

There are a few general rules with units. Those named after people (Watt, Joule, Amp, Coulomb, Kelvin, Celsius etc) are, by convention spaced with a single space after the numeric value, whereas those units not named after an individual are not.
No. There is always a space between the numeric value and the unit symbol, for all units.
Sources: http://ukma.org.uk/d...style-guide.pdf
<br />
http://www.npl.co.uk...si-conventions/

Edited by djh99, 14 August 2015 - 12:10 PM.


#11 joiner

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Posted 14 August 2015 - 01:08 PM

There is a problem with that 'style guide'. Namely the invitation to create a situation that could lead to an error earlier advised against, as in...


Which units to use?

Because of the flexibility of the metric system there is a choice of possible units to describe something - e.g. the width of a kitchen unit could be given as 500 mm, or 50 cm, or 0.5 m. The following advice is offered:

Avoid unnecessarily large numbers or trailing zeroes - e.g. write 4 m rather than 4000 mm. For clothes sizes, prefer 95 cm to 950 mm.

Use whole numbers and avoid decimal points if possible - e.g. write 25 mm rather than 2.5 cm.


So how would this person express 4015 mm? As 4.015 m? 40.15 cm?

Expressing it in mm takes up no more space than any alternative format but avoids the potentially serious pitfall of an "accidental" mark on a drawing being seen as a decimal point, quite apart from the fact that if all dimensions on a drawing are expressed in the same format you know instantly what you're looking at.

Edited by joiner, 11 November 2015 - 06:42 AM.


#12 Nickfromwales

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Posted 06 January 2016 - 10:29 PM

Another bump.
Some people are struggling to post emoticons, so just to let you know the way to enter them via a standard text :)
I'll insert gaps in the examples so they don't convert, just removed the gaps to display.
Due to the forum software I have to break this into chunks or else it exceeds the number of permitted emoticons per post.
: ) = :)
: ( = :(
: o = :o
: p = :P



#13 Nickfromwales

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Posted 06 January 2016 - 10:30 PM

: D = :D
: lol : = :lol:
: rolleyes : = :rolleyes:
: ph34r : = :ph34r:
B ) = B)



#14 Nickfromwales

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    Short cuts take three times longer.....Fact

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Posted 06 January 2016 - 10:32 PM

: wacko : = :wacko:
: blink : = :blink:
: wub : = :wub:
: huh : = :huh:
One I like to call "joiner"......: angry : = :angry: ( brought on by auto spell and most mobile caused typos and when threads digress just that BIT too far ).
There are a few more but the symbols aren't available on an iPad keyboard.....or are they ?!?!
Regards, nick.

Edited by Nickfromwales, 06 January 2016 - 10:38 PM.


#15 SteamyTea

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Posted 06 January 2016 - 10:34 PM

The big question is which ones to use. The normal smile and sad face are easy. The rest I usually use a bit randomly, apart from the wink.

#16 joiner

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Posted 27 January 2016 - 08:46 AM

Bump. ;)