What is OTTV calculation?
What is OTTV calculation?
The OTTV of an entire building is calculated by the weighted average of the OTTVs of the external walls and the roof of a building. Some countries in the Central America, including Jamaica and Ivory Coast, had developed their building energy standards using OTTV as a part of the requirements [4].
What is OTTV and rttv?
However, the fundamental difference between RTTV and OTTV is that, the RTTV methodology assumes that residential units are not mechanically cooled from November to March inclusive while the OTTV assumes space-conditioning is required within a commercial building or hotel throughout the year primarily during the day.
How do I get better at OTTV?
So, the OTTV can be reduced by using lower wall U-value and lower wall absorption. Wall U-value and wall absorption can be reduced by thermal insulation the concrete brick for wall and using the light colour of wall external surface finish. Moreover introducing shades and coating on glass can reduce solar heat gain.
How to calculate OTTV for wall?
- OTTVi = 15α (1- WWR) Uw + 6 (WWR) Uf + (194 x CF x WWR x SC)
- OTTV =
- +
- +
- Heat.
- Conduction.
- through.
- Walls.
What is Envelope Thermal Transfer Value?
Envelope Thermal Transfer Value (ETTV) 4.1 The ETTV takes into account the three basic components of heat gain through the external walls and windows of a building. These are: heat conduction through opaque walls, heat conduction through glass windows, solar radiation through glass windows.
What is Au value?
A U-value is a sum of the thermal resistances of the layers that make up an entire building element – for example, a roof, wall or floor. It also includes adjustments for any fixings or air gaps. The lower the U-value, the better insulated the building element.
What is Ettv value?
Envelope Thermal Transfer Value (ETTV) These are: heat conduction through opaque walls, heat conduction through glass windows, solar radiation through glass windows. 2.2. These three components of heat input are averaged over the whole.
What is an over all thermal transfer value or OTTV?
Abstract. Overall Thermal Transfer Value (OTTV) is a measure of average heat gain into a building through the building envelope. It is a widely adopted measure in many countries for enhancing energy-efficient building design.
How is envelope U value calculated?
U = Thermal Transmittance (W/m²·K)*
How do you calculate Ettv?
Online ETTV U-value calculator
- Outside airVertial wallHigh emissivityR = 0.044 (m2K)/W.
- Metal: aluminium alloyk = 211 W/(m⋅K)d = 2 mmR = 0.000 (m2K)/W.
- Plaster: perlitek = 0.115 W/(m⋅K)d = 10 mmR = 0.087 (m2K)/W.
- Brick, dry (covered by plaster/tile)k = 0.807 W/(m⋅K)d = 80 mmR = 0.099 (m2K)/W.
What is Au value in insulation?
What is the R-Value of 100mm kingspan?
4.30 0.023
Product Application
| Product | R Value (mK/W) | Thermal Conductivity (W/mK) |
|---|---|---|
| TP10 100mm | 4.30 | 0.023 |
| TP10 105mm | 4.55 | 0.023 |
| TP10 110mm | 4.75 | 0.023 |
| TP10 115mm | 5.00 | 0.023 |
