IE Q Credit 8.1: Daylight and Views—Daylight 1 Point Intent To

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试卷: IEQ 室内环境质量[查看]
IE Q Credit 8.1: Daylight and Views—Daylight
1 Point

Intent
To provide for the building occupants with a connection between indoor spaces and the outdoors through the
introduction of daylight and views into the regularly occupied areas of the building.

Requirements
Through 1 of the 4 options, achieve daylighting in at least the following spaces1:

Regularly Occupied Spaces; Points
75% 1

OPTION 1. Simulation
Demonstrate through computer simulations that the applicable spaces achieve daylight illuminance levels of a minimum of 10 footcandles (fc) and a maximum of 500 fc in a clear sky condition on September 21 at 9 a.m. and 3 p.m.Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However, designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 10 fc illuminance level.
OR
OPTION 2. Prescriptive
For side-lighting zones:
-- Achieve a value, calculated as the product of the visible light transmittance (VLT) and window-to-floor area
ratio (WFR) between 0.150 and 0.180.
0.150 < VLT x WFR < 0.180
-- The window area included in the calculation must be at least 30 inches above the floor.
-- In section, the ceiling must not obstruct a line that extends from the window-head to a point on the floor
that is located twice the height of the window-head from the exterior wall as measured perpendicular to the
glass (see diagram on next page).

Daylighting images.bmp

-- Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However,
designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 0.150 value.
For top-lighting zones:
-- The top-lighting zone under a skylight is the outline of the opening beneath the skylight, plus in each direction the lesser of (see diagram below):
-- 70% of the ceiling height,
-- 1/2 the distance to the edge of the nearest skylight,
-- The distance to any permanent partition that is closer than 70% of the distance between the top of the
partition and the ceiling.

Daylighting images.bmp

-- Achieve skylight coverage for the applicable space (containing the top-lighting zone) between 3% and 6% of the total floor area.
-- The skylight must have a minimum 0.5 VLT.
-- A skylight diffuser, if used, must have a measured haze value of greater than 90% when tested according to ASTM D1003.
OR
OPTION 3. Measurement
Demonstrate through records of indoor light measurements that a minimum daylight illumination level of 10 fc and a maximum of 500 fc has been achieved in the applicable spaces. Measurements must be taken on a 10-foot grid and shall be recorded on building floor plans.
Provide glare control devices to avoid high-contrast situations that could impede visual tasks. However, designs that incorporate view-preserving automated shades for glare control may demonstrate compliance for only the minimum 10 fc illuminance level.
OR
OPTION 4. Combination
Any of the above calculation methods may be combined to document the minimum daylight illumination in the applicable spaces.

Potential Technologies & Strategies
Design the building to maximize interior daylighting. Strategies to consider include building orientation, shallow floor plates, increased building perimeter, exterior and interior permanent shading devices, high-performance glazing, and high-ceiling reflectance values; ly, additionally, automatic photocell-based controls can help to reduce energy use. Predict daylight factors via manual calculations or model daylighting strategies with a physical or computer model to assess footcandle levels and daylight factors achieved.


IEQ C8.1: 采光和视野 — 采光
1 Point

目的
通过采光和视野引入建筑常用区域，为建筑用户提供一个室内与室外联系。

要求
通过四个选项之一，在以下区域实现采光：
常用空间得分
75% 1
选项1. 模拟
采用计算机模拟，说明常用空间75%以上，自然采光照度最低可达到25烛光英尺(fc)(269lux)，
最高照度小于500烛光英尺(fc)(5380lux)，计算条件是11月21日上午9点至下午3点间，晴空天
气。照度低于或高于这个范围的不能计入达标面积。
但是，如采取了保持视野的眩光遮阳自动控制装置，可以视为仅符合最低25fc(269lux)的照度
水平。
或者
选项2. 指标
结合侧光和/或顶光，实现总采光区域(地板面积满足以下要求)，占所有常用空间的至少75%。.
对于侧光采光区域（见下图）:
-- 采光区域的可见光透射率(VLT)与窗地比(WFR)的乘积在0.150～0.180之间，窗面积
的计算只能包括高于地面30英寸的部分。
0.150 < VLT x WFR < 0.180
-- 连线窗头与窗面平行面与楼板交线处，距离为2倍于窗头距地高度，垂直于窗面，要
求吊顶部分不得与该连线有交叉.
-- 有阳光非直射，和/或眩光控制装置，确保采光质量。
图一.
对于天光采光区域（见下图）:
-- 天光下的采光区域以天光洞口投影边线，加上每个方向以下较小者：
-- 70%的顶高,
或者
-- 到最近天光边界的1/2距离，
或者
-- 到任何固定型不透明物体的距离大于物体顶至少顶板距离70%的位置
-- 屋面天光洞口面积占屋面面积3%～6%，并未可见光透射率在0.5及以上，
-- 天光洞口间距不大于顶板高度的1.4倍􀋈
-- 如采用散光器，则按ASTM D1003标准，其检测雾化值大于90%，避免天光散光器的直接视线。
不能采用日光的工作区域面积除外。
图二.

或者
选项3. 测量
采用室内光测量记录，说明所有常用区域的75%面积能够有最低25fc的自然光。测量应对所有
常用区域采用10英尺的网格，并记录在建筑平面图中。
只有符合照度要求的相关房间与空间面积才能被纳入计算。
选用这个选项的工程，自然采光非直射，和/或有眩光控制装置，以免产生高反差情况。不适
宜自然采光下工作的区域面积除外。
或者
选项4. 混合
以上的各计算方法可以混合使用，以证明75%以上的所有常用空间复合最低采光照度。每个空
间计算方法的不同必须清楚地记录在所有建筑平面中。
所有情形下，所有房间和空间的部分面积满足75%的采光，其总面积即可计入面积计算中。
所有情形下，应有眩光控制装置避免高反差光影响视力工作，但不利于日光工作的空间除外。

技术措施和策略
设计设计最大化自然采光，措施有建筑朝向、窄化建筑楼面、增加建筑周长、外部和内部固定
遮阳装置、高性能玻璃、高反射顶面，另外，自动感光控制也能降低能耗。手工计算或计算机
物理模型模拟，可预测采光因素，以评估照度水平和采光系数。