From a561aaf1283e74815d2c54d6e80d2947c2f38fb7 Mon Sep 17 00:00:00 2001 From: Zane Meyers Date: Thu, 18 Dec 2025 17:14:55 -0500 Subject: [PATCH] vault backup: 2025-12-18 17:14:55 --- .obsidian/bookmarks.json | 5 + 2025-12-18.md | 64 ++++++++++ ...ial-science-for-construction-estimating.md | 2 + actuarial-science.md | 4 + bid-price-modeling.md | 2 +- carbon-monoxide-detection-takeoff.md | 2 +- consolidate-estimating-thoughts.md | 5 +- decrease-in-sigma.md | 88 +++++++++++++ distributed-antenna-systems-takeoff.md | 20 +-- electrical-takeoff.md | 2 +- emergency-systems-research.md | 2 + feeders-takeoff.md | 2 +- fire-alarm-takeoff.md | 76 ++++++----- fire-resistive-wiring-methods-takeoff.md | 2 +- fixture-designations.md | 2 +- fixtures-takeoff.md | 2 +- grounding-takeoff.md | 2 +- lighting-controls-takeoff.md | 2 +- lightning-protection-takeoff.md | 2 +- low-voltage-takeoff.md | 2 +- me-isms.md | 1 + ...-management-for-construction-estimating.md | 79 +----------- risk-oriented-estimating.md | 120 ------------------ standalone-systems-takeoff.md | 2 +- ...al-modeling-for-construction-estimating.md | 16 +++ subfeeds-takeoff.md | 2 +- switchgear-takeoff.md | 2 +- telecom-takeoff.md | 2 +- ...transparency-in-construction-estimating.md | 33 +++-- two-way-takeoff.md | 8 +- uncertainty-in-construction-estimating.md | 62 +++++++++ uncertainty.md | 13 -- units-takeoff.md | 2 +- 33 files changed, 342 insertions(+), 288 deletions(-) create mode 100644 2025-12-18.md create mode 100644 decrease-in-sigma.md delete mode 100644 risk-oriented-estimating.md rename estimating-ethics.md => transparency-in-construction-estimating.md (78%) create mode 100644 uncertainty-in-construction-estimating.md diff --git a/.obsidian/bookmarks.json b/.obsidian/bookmarks.json index a5315c5..954c5ed 100644 --- a/.obsidian/bookmarks.json +++ b/.obsidian/bookmarks.json @@ -14,6 +14,11 @@ "type": "file", "ctime": 1761313177282, "path": "nfpa-70_national-electric-code.md" + }, + { + "type": "file", + "ctime": 1766074735360, + "path": "consolidate-estimating-thoughts.md" } ] } \ No newline at end of file diff --git a/2025-12-18.md b/2025-12-18.md new file mode 100644 index 0000000..dda6597 --- /dev/null +++ b/2025-12-18.md @@ -0,0 +1,64 @@ +--- +id: +aliases: [] +title: "2025-12-18" +tags: + - authorship/original + - destiny/permanent + - status/draft + - type/daily +--- +# 2025-12-18 + +## 2025-12-18 08:32 + +[[uncertainty-in-construction-estimating]] + +## 2025-12-18 10:38 + +#topic/meta + +I definitively think my new approach +of putting nascent ideas in daily notes +rather than separate fleeting notes +is superior. + +The unfortunate reality is I'll never look at most of them again, +so better that they don't crowd out my main notes. + +## 2025-12-18 14:18 + +What interests me most in [[construction-estimating]] +is an idea you might call "estimating golf": +the goal is to produce a satisfactory[^1] estimate, +the estimator can not view the project documents +and must ask questions about the job +(answerable in a sentence or less) +of a neutral party ("the reader"). +The estimator fails if the estimate is unsatisfactory[^1], +but otherwise is scored by number of questions asked. + +[^1]: satisfactory in terms of accuracy and precision, + according to the standards of the organization. + a control estimate must be prepared accordingly + by a neutral party ("the control"). + +You could further imagine different brackets +for required accuracy and precision, +whether organization historicals are freely available +or must be questioned like project details. + +The most interesting part of this problem is choosing when to stop, +since it requires one to estimate their certainty of their estimate. + +## 2025-12-18 15:22 + +PDI has moved up the schedule to transition to Accubid Anywhere +and will be signing a contract with Trimble in late January. + +[Drawer AI | Automated Electrical Takeoff & Estimating](https://drawer.ai/) + +## 2025-12-18 15:30 + +[Kip (unit) - Wikipedia](https://en.wikipedia.org/wiki/Kip_\(unit\)) +[Construction Cost Estimating](https://www.quantity-takeoff.com/index.htm) \ No newline at end of file diff --git a/actuarial-science-for-construction-estimating.md b/actuarial-science-for-construction-estimating.md index 354cc35..bac4a27 100644 --- a/actuarial-science-for-construction-estimating.md +++ b/actuarial-science-for-construction-estimating.md @@ -22,3 +22,5 @@ In this way, projects are better compared to _insurance accounts_. * cost of individual service is uncertain * cost to customer must be minimized + +![[decrease-in-sigma#^pdf]] \ No newline at end of file diff --git a/actuarial-science.md b/actuarial-science.md index 5219847..8235b48 100644 --- a/actuarial-science.md +++ b/actuarial-science.md @@ -13,6 +13,10 @@ tags: [actuarial science](https://en.wikipedia.org/wiki/Actuarial_science) +Divorced from its traditional context of insurance, +actuarial science is determining the optimal price of a service +given [[uncertainty|uncertain]] cost. + ## Terms * [discounted cash flow](https://en.wikipedia.org/wiki/Discounted_cash_flow) diff --git a/bid-price-modeling.md b/bid-price-modeling.md index c8b2ca3..30a1af1 100644 --- a/bid-price-modeling.md +++ b/bid-price-modeling.md @@ -55,7 +55,7 @@ $$ \Phi : \mathcal{P}([0,\infty)) \to [0,\infty), $$ -mapping a cost distribution $\mu_C$ to a scalar. +mapping a cost distribution $\mu_C$ to a **scalar** (a single value). Examples of such functionals include: diff --git a/carbon-monoxide-detection-takeoff.md b/carbon-monoxide-detection-takeoff.md index 0d82011..137257a 100644 --- a/carbon-monoxide-detection-takeoff.md +++ b/carbon-monoxide-detection-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/standalone-systems + - occupational/takeoff - status/draft - type/guide title: Carbon Monoxide Detection Takeoff diff --git a/consolidate-estimating-thoughts.md b/consolidate-estimating-thoughts.md index 7de1386..2aaea28 100644 --- a/consolidate-estimating-thoughts.md +++ b/consolidate-estimating-thoughts.md @@ -30,11 +30,11 @@ Remove estimating-specific content from irrelevant notes. Create and use cross-topic notes for complex thoughts: +* [[uncertainty-in-construction-estimating]] + * [[actuarial-science-for-construction-estimating]] - * [[risk-oriented-estimating]] * [[risk-management-for-construction-estimating]] - * [[risk-oriented-estimating]]: resource allocation * [[auction-theory-for-construction-estimating]] * [[bid-process-strategy]] @@ -58,7 +58,6 @@ Create and use cross-topic notes for complex thoughts: * [[statistical-modeling-for-construction-estimating]] * [[transparency-in-construction-estimating]] - * [[estimating-ethics]] ### Orphaned Notes diff --git a/decrease-in-sigma.md b/decrease-in-sigma.md new file mode 100644 index 0000000..47abfcf --- /dev/null +++ b/decrease-in-sigma.md @@ -0,0 +1,88 @@ +# Decrease in Sigma + +```tikz +\usepackage{pgfplots} +\pgfplotsset{compat=1.16} + +\begin{document} +\begin{tikzpicture} + \begin{axis}[ + width=13cm, + height=7cm, + axis lines=middle, + xlabel={$x$}, + ylabel={$\varphi(x;\mu,\sigma)$}, + xmin=-6, xmax=6, + ymin=0, ymax=0.85, + samples=400, + domain=-6:6, + legend style={draw=none, fill=none, at={(0.98,0.98)}, anchor=north east}, + legend cell align=left, + ytick=\empty, + ] + + % Normal PDF: (1/(sigma*sqrt(2*pi))) * exp(-(x-mu)^2/(2*sigma^2)) + + \addplot[thick] + { (1/(1.8*sqrt(2*pi))) * exp(-((x-0.8)^2)/(2*1.8^2)) }; + \addlegendentry{$\mu=0,\ \sigma=1.8$} + + \addplot[thick, dashed] + { (1/(0.8*sqrt(2*pi))) * exp(-((x-0.8)^2)/(2*0.8^2)) }; + \addlegendentry{$\mu=0,\ \sigma=0.8$} + + \end{axis} +\end{tikzpicture} +\end{document} +``` + +^pdf + +```tikz +\usepackage{pgfplots} +\pgfplotsset{compat=1.16} + +\pgfmathdeclarefunction{erfapprox}{1}{% + \pgfmathparse{% + % save sign and work with |x| + ( (#1<0) ? -1 : 1 ) + * ( 1 - (1 + 0.278393*abs(#1) + 0.230389*abs(#1)^2 + 0.000972*abs(#1)^3 + 0.078108*abs(#1)^4)^(-4) ) + }% +} + +% Normal CDF using erf approximation: +% F(x;mu,sigma) = 0.5*(1 + erf((x-mu)/(sigma*sqrt(2)))) +\pgfmathdeclarefunction{normcdf}{3}{% + \pgfmathparse{ 0.5*(1 + erfapprox((#1-#2)/(#3*sqrt(2)))) }% +} + +\begin{document} +\begin{tikzpicture} + \begin{axis}[ + width=13cm, + height=7cm, + axis lines=middle, + xlabel={$x$}, + ylabel={$F(x;\mu,\sigma)$}, + xmin=-6, xmax=6, + ymin=0, ymax=1.05, + samples=400, + domain=-6:6, + legend style={draw=none, fill=none, at={(0.02,0.98)}, anchor=north west}, + legend cell align=left, + ytick={0,0.5,1}, + ] + + % Normal CDF: 0.5*(1 + erf((x-mu)/(sigma*sqrt(2)))) + \addplot[thick] + { normcdf(x,0,1.8) }; + \addlegendentry{$\mu=0,\ \sigma=1.8$} + + \addplot[thick, dashed] + { normcdf(x,0.8) }; + \addlegendentry{$\mu=0,\ \sigma=0.8$} + + \end{axis} +\end{tikzpicture} +\end{document} +``` \ No newline at end of file diff --git a/distributed-antenna-systems-takeoff.md b/distributed-antenna-systems-takeoff.md index f3d2997..e7994c9 100644 --- a/distributed-antenna-systems-takeoff.md +++ b/distributed-antenna-systems-takeoff.md @@ -5,7 +5,7 @@ aliases: tags: - authorship/original - destiny/permanent - - occupational/takeoff/standalone-systems + - occupational/takeoff - status/draft - type/guide title: Distributed Antenna Systems (DAS) Takeoff @@ -22,17 +22,19 @@ title: Distributed Antenna Systems (DAS) Takeoff > [!info] Cellular Systems > Less common than ERRCS are "cellular DAS" systems +`COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/... + ## Backbone ### FACR to Every Elevator Shaft -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/`FACR TO ELEV PIT = ...` +1. .../`FACR TO ELEV PIT = ...` * **Length** = _Match Fire Alarm takeoff Length_ * **Count** = _Match Fire Alarm takeoff Count_ ### FACR to Every Staircase -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/`FACR TO STAIRWELL = ...` +1. .../`FACR TO STAIRWELL = ...` * **Length** = _Match Fire Alarm takeoff Length_ * **Count** = _Match Fire Alarm takeoff Count_ @@ -40,22 +42,22 @@ title: Distributed Antenna Systems (DAS) Takeoff 1. * `Area` = "Typical - Stairwells Building Even Levels" - `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/`STAIRWELL RISER EVERY 2 FLRS = ...` + .../`STAIRWELL RISER EVERY 2 FLRS = ...` * **Count** = Each stairwell ### FACR to Electric Room -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/`FACR TO 2HR-RATED RM = ...` - * **Length** = _Match Fire Alarm takeoff Length_ +1. .../`FACR TO 2HR-RATED RM = ...` + * **Length** = _Match Fire Alarm Terminal Cabinet takeoff Length_ ### Electric Room Riser to Every Floor -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/`2HR-RATED RM RISER TO EVERY FLR = ...` +1. .../`2HR-RATED RM RISER TO EVERY FLR = ...` * **Count** = Each Electric Room ### Top 2H Rated Room To Roof -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/`TOP 2HR RATED RM TO ROOF = ...` +1. .../`TOP 2HR RATED RM TO ROOF = ...` * **Length** = Top level ceiling height to structure (minimum 15ft) ## Horizontal @@ -64,5 +66,5 @@ title: Distributed Antenna Systems (DAS) Takeoff > Usually only for cellular DAS. > Confirm takeoff requirement with [[pdi-estimating#Bid Estimating|Bid]]. -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`DAS ASSEMBLIES`/`CORRIDORS ...` +1. .../`CORRIDORS ...` * **Length** = Length measured for every corridor/garage diff --git a/electrical-takeoff.md b/electrical-takeoff.md index 5e73328..9f25a77 100644 --- a/electrical-takeoff.md +++ b/electrical-takeoff.md @@ -5,7 +5,7 @@ title: Electrical Takeoff tags: - authorship/original - destiny/permanent - - occupational/takeoff/electrical + - occupational/takeoff - status/draft - type/guide --- diff --git a/emergency-systems-research.md b/emergency-systems-research.md index 89cb679..3a6b639 100644 --- a/emergency-systems-research.md +++ b/emergency-systems-research.md @@ -16,6 +16,8 @@ title: Emergency Systems Research > * [[two-way-takeoff]] > * [[distributed-antenna-systems-takeoff]] +[[wiring-method-selection]] + 1. Find Fire Alarm plans (if present) 2. Locate the following rooms: * Fire Command Center (FCC) diff --git a/feeders-takeoff.md b/feeders-takeoff.md index 5a405e9..80d778a 100644 --- a/feeders-takeoff.md +++ b/feeders-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/feeders + - occupational/takeoff - status/draft - type/guide title: Feeders Takeoff diff --git a/fire-alarm-takeoff.md b/fire-alarm-takeoff.md index a389e62..e98c50c 100644 --- a/fire-alarm-takeoff.md +++ b/fire-alarm-takeoff.md @@ -1,13 +1,13 @@ --- id: aliases: [] +title: Fire Alarm Takeoff tags: - authorship/original - destiny/permanent - - occupational/takeoff/fire-alarm + - occupational/takeoff - status/draft - type/guide -title: Fire Alarm Takeoff --- # Fire Alarm Takeoff @@ -28,46 +28,58 @@ _Mid Rise, High Density (Wood frame):_ Free air, conduit only where required. ## Backbone -Put all backbone takeoff in the `Area` of the Fire Command Center. Include [[sleeving-takeoff]] as necessary. +`COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/... + ### Fire Command Center -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`HEAD END EQUIP`/`... HEAD END` +1. * `Area` = As shown. + * `Phase` = As shown. + + .../`HEAD END EQUIP`/`... HEAD END` ### Generator Room -1. `Area` = Same as FACR +1. * `Area` = Same as FACR. + * `Phase` = Same as FACR. - `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`GENERATOR ROOM ...` + .../`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`GENERATOR ROOM ...` ### Fire Pump Room -1. `Area` = Same as FACR +1. * `Area` = Same as FACR. + * `Phase` = Same as FACR. - `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FIRE PUMP ROOM ...` + .../`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FIRE PUMP ROOM ...` ### Elevator Control Rooms > Also "Elevator Machine Room" +* `Area` = Same as FACR. +* `Phase` = Same as FACR. + For each Elevator Control Room (ECR): -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`ELEV CONTROL ROOM ...` +1. .../`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`ELEV CONTROL ROOM ...` * **Count** = 1 -2. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FACR TO ELEV CONTROL RM ...` +2. .../`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FACR TO ELEV CONTROL RM ...` * **Length** = Length measured from the most distant points of the FACR and ECR. - * Input adder length to reach the level of the ECR (Minimum 15ft). + * Input adder length to reach the level of the ECR (Minimum 15ft). ### Elevator Shafts +* `Area` = Same as FACR. +* `Phase` = Same as FACR. + For each elevator shaft: -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`ELEV SHAFT ...` +1. .../`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`ELEV SHAFT ...` * **Count** = 1 -2. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FACR TO ELEV SHAFT ...` +2. .../`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FACR TO ELEV SHAFT ...` * **Length** = Length measured from the most distant points of the FACR and elevator shaft. * Input adder length to reach the level of the shaft (Minimum 15ft). @@ -91,7 +103,10 @@ For each elevator shaft: For each stairwell: -1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FACR TO STAIRWELLS 1" CONDUIT ...` +1. * `Area` = Same as FACR. + * `Phase` = Same as FACR. + + .../`GEN, ELEV, FIRE PUMP & FA ROOM ASSEMBLIES`/`FACR TO STAIRWELLS 1" CONDUIT ...` * **Length** = Length measured from the most distant points of the FACR and stairwell. * Input adder length to reach the level of the stairwell (Minimum 15ft). @@ -104,8 +119,8 @@ For each stairwell: 1. Horizontal: - * `Area` = Same as FACR - + * `Area` = Same as FACR. + `... HORIZONTAL RUN` * **Length** = Length measured from FACR to all electrical rooms @@ -128,10 +143,10 @@ For each stairwell: ## Central Monitoring Loop > [!important] -> Garden Style only. +> Garden Style only. > Fire Alarm Control Panels from each building will send a signal to a central location. -> +> > In case of an emergency, > the fire department will go to the central fire alarm station > and find out what the issue is. @@ -141,32 +156,23 @@ For each stairwell: ### Smoke Detectors 1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`INITIATING DEVICES WITH WIRE - ...`/`SMOKE DETECTOR W/ BASE - ...` - -_Design Build:_ -Count every stairwell at every level. + * **Count:** As shown, otherwise (1) every stairwell at every level. ### Pull Stations 1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`INITIATING DEVICES WITH WIRE - ...`/`PULL STATION - ...` - -_Design Build:_ -Count every stairwell at every level -and every exterior exit. + * **Count:** As shown, otherwise (1) every stairwell at every level and every exterior exit. ### Flow/Tamper Switches -No free-air. If wood frame, take off as EMT. - -_Design Build:_ -Count every stairwell at every level. +1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`INITIATING DEVICES ...`/`ADDRESSABLE DUAL MONITOR MODULE - FLOW/TAMPER - ...` (No free-air) + * **Count:** As shown, otherwise (1) every stairwell at every level. ### Magnetic Door Holders 1. `COMMON ASSEMBLIES`/`FIRE ALARM & DAS SYSTEMS`/`INDICATING DEVICES WITH WIRE - ...`/`MAGNETIC DOOR HOLDER - ...` - -_Design Build:_ -Count 2 for every set of double doors. -(Typical of elevator lobbies and corridors) + * **Count:** As shown, otherwise (2) every set of double doors. + (Typical of elevator lobbies and corridors) ### Horns, Speakers, and Strobes @@ -177,8 +183,8 @@ _Design Build (method 1):_ * measure with circles on Bluebeam * or divide relevant SF area by 4415 * $\pi(\frac{75}{2})^2 \approx 4415$ -* every elevator lobby, -* and every BOH room on the first floor and garage levels. +* every elevator lobby, and +* every BOH room on the first floor and garage levels. _Design Build (alternative method):_ * 15ft from end of corridor, diff --git a/fire-resistive-wiring-methods-takeoff.md b/fire-resistive-wiring-methods-takeoff.md index e2d55fe..6d2188d 100644 --- a/fire-resistive-wiring-methods-takeoff.md +++ b/fire-resistive-wiring-methods-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/electrical + - occupational/takeoff - status/draft - type/guide title: Fire Resistive Wiring Methods Takeoff diff --git a/fixture-designations.md b/fixture-designations.md index ffd598c..3f02402 100644 --- a/fixture-designations.md +++ b/fixture-designations.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/fixtures + - occupational/takeoff - status/draft - type/guide title: Fixture Designations diff --git a/fixtures-takeoff.md b/fixtures-takeoff.md index 74f0b30..947496e 100644 --- a/fixtures-takeoff.md +++ b/fixtures-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/fixtures + - occupational/takeoff - status/draft - type/guide title: Fixtures Takeoff diff --git a/grounding-takeoff.md b/grounding-takeoff.md index 624ef76..5e22a14 100644 --- a/grounding-takeoff.md +++ b/grounding-takeoff.md @@ -5,7 +5,7 @@ title: Grounding Takeoff tags: - authorship/original - destiny/permanent - - occupational/takeoff/feeders + - occupational/takeoff - status/draft - type/guide --- diff --git a/lighting-controls-takeoff.md b/lighting-controls-takeoff.md index fd312f0..b05eaed 100644 --- a/lighting-controls-takeoff.md +++ b/lighting-controls-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/electrical + - occupational/takeoff - status/draft - type/guide title: Lighting Controls Takeoff diff --git a/lightning-protection-takeoff.md b/lightning-protection-takeoff.md index d83fbca..f198420 100644 --- a/lightning-protection-takeoff.md +++ b/lightning-protection-takeoff.md @@ -3,7 +3,7 @@ id: aliases: [] tags: - destiny/permanent - - occupational/takeoff/lightning-protection + - occupational/takeoff - status/draft - type/guide - authorship/original diff --git a/low-voltage-takeoff.md b/low-voltage-takeoff.md index 9a79c64..b240bb5 100644 --- a/low-voltage-takeoff.md +++ b/low-voltage-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/low-voltage + - occupational/takeoff - status/draft - type/guide title: Low Voltage Takeoff diff --git a/me-isms.md b/me-isms.md index b3ec8ea..86b3041 100644 --- a/me-isms.md +++ b/me-isms.md @@ -12,3 +12,4 @@ tags: # Me-isms * (when misunderstood) "No, no, no." +* certainly diff --git a/risk-management-for-construction-estimating.md b/risk-management-for-construction-estimating.md index c8e6c3c..1dac75a 100644 --- a/risk-management-for-construction-estimating.md +++ b/risk-management-for-construction-estimating.md @@ -15,84 +15,15 @@ tags: Cross-topic of [[risk-management]] and [[construction-estimating]]. -## Prioritizing Tasks - -ROE prioritizes estimating tasks by their contribution to _cost certainty_. - -### Estimating as Risk Mitigation +## Estimating as Risk Mitigation * reduce risk of wasted estimation effort due to bid loss (prefer lower bid) * reduce risk of project overrun (prefer higher bid) -Estimating resources are allocated by Return on Mitigation (RoM) +Estimating resources should be allocated +according to Return on Mitigation (RoM), +that is, their contribution to _cost certainty_. -### Determining Necessary Detail - -ROE determines the appropriate level of [[estimating-detail]] -given an organization's [[risk#Risk Tolerance]]. - -#### EVI Takeoff - -Expected value of information (EVI) - -#### Takeoff Optimization - -For systems where EVI analysis determines manual takeoff is still necessary, -optimizations can be made to decrease the required effort of takeoff, -and thus the opportunity cost of takeoff. - -See [[optimal-estimating-patterns]] for more. - -# Estimating Detail - -The acceptable level of detail of an estimate -in [[construction-estimating]] is a contentious subject. -What's worse, estimators often disagree -on what makes an estimate more detailed than another. - -The commonly repeated answer is this: - -> As detailed as possible, -> given required turnaround and available estimating resources. - -This analysis is flawed -because it implies more time always ought to be preferred, -when the reality is that when considering larger organizational factors, -ideal estimate certainty is likely far lower than most expect. - -The correct answer involves optimizing for these factors: -* value of increased bid certainty -* value of increased estimate volume - -An estimate's detail is irrelevant to its quality. -A less detailed estimate is a more [[risk|risky]] bid, -but it is not the role of the estimator to determine acceptable risk. - -## Experiment - -Perform a system takeoff (lighting for example) in exacting detail, -the maximum amount you would ever consider using, -and measure the time required to do so, -as well as the cost of the scope. - -Have another estimator takeoff the same scope -using the proposed time saving strategy. - -Repeat the test on additional projects. - -Treat the detailed takeoff as the true value -and find the error of the time saving strategy. - -$\frac{d\sigma}{dt}$ - -### Expectation - -Time-saving strategies will overestimate or underestimate detailed takeoff -depending on the assumptions used in their creation. - -## Human Error - -It is commonly understood that a "detailed takeoff" -is more "accurate" than a square foot estimate. +$\text{Efficiency} = -1 \times \frac{d\sigma}{dt}$ diff --git a/risk-oriented-estimating.md b/risk-oriented-estimating.md deleted file mode 100644 index f1f8829..0000000 --- a/risk-oriented-estimating.md +++ /dev/null @@ -1,120 +0,0 @@ ---- -id: risk-oriented-estimating -aliases: [] -tags: - - destiny/fleeting - - status/incomplete - - topic/estimating - - topic/risk - - type/supertopic - - authorship/original -title: Risk Oriented Estimating ---- -# Risk Oriented Estimating - -## Abstract - -Risk-Oriented Estimating (ROE), -is a [[estimating-methodologies|methodology]] -for [[construction-estimating]] which: -* prioritizes estimating tasks, -* determines necessary [[estimating-detail]] - -ROE leans heavily on [[uncertainty#Value of Information]], -which challenges the natural tendency to fear even the smallest risk -with the reality of the **cost of certainty**. - -ROE does not endorse common shortcuts that round up to "cover" uncertainty, -as these ultimately _increase_ risk by inflating the apparent project cost, -increasing the probability of loss to a competitor. - -%% - -## TALK - -This note currently gets too far into the weeds -of critiquing common practice. - -%% - -## Potential Objections - -Objections to the use of historical data in new estimates are not unfounded. -A framework to do so competently and consistently -does not currently exist. -Nor does the software necessary to utilize such a framework efficiently. - -The goal in and of itself ought not be controversial, however. -Businesses regularly make far riskier decisions based on projections -informed by the same data. - -By definition, if one could adjust historical pricing accurately for all dependent factors, -the adjusted price would be accurate to the new job. - -The issue is that there are hundreds to thousands of potential dependent factors. -A nonstarter for uncreative minds, -but a worthwhile challenge for estimators truly passionate about their field. - -It is unique of construction estimating among similar fields -that analysis and discussion of risk is largely absent from pre-approval review. -The tools common of our trade almost always lack the means -to quantify the dollar amount implications of our assumptions. - -There is an enormous gap in complexity between pure square foot pricing and -[[traditional-estimating-methods]] that tools do not exist to bridge. - -At all points in the estimating process, -It should be possible to give a confident budget. - -## In Comparison - -For most contractors, there is not usually a minimum amount of project detail -required to provide a budget for a project -Estimators know what the most likely and most expensive options are for a given scope -and can fill in the detail required for item-oriented takeoff. -This is called an **assumption** and is the basis of cost estimation. - -Assumptions are fundamentally incompatible with item-oriented estimating -as it is commonly implemented. -It is not possible to compare price possibilities -except by creating separate takeoffs and breakdowns for each one. - -Rather than building the job one `WOOD NAIL - GALV STEEL - #10 - 5-INCH` at a time, -risk-oriented estimating focuses on reducing risk of a decent budget. - -Risk-oriented estimating understands a `NAIL` like an estimator: -an abstract item in a certain price range requiring labor in a certain hour range. - -A practitioner of this style would find -that the impact of such details on the final price of a job -are so low as to be trivial. -Not to say that they shouldn't be addressed, -only that they ought not be addressed before more significant factors. - -Risk is a measure of the effect of uncertainty on outcome. -Uncertainty being a necessity of estimating, -the language and tools that we use -must facilitate discussions of risk management. -In estimation in fields other than construction -it is common to give an estimate as a _confidence interval_, -a range in which a result has a certain percentage chance to fall. -This interval can be determined from a population of possible prices. - -The _accuracy_ of a risk-oriented estimate remains roughly the same -(approaching 100% with continuous input) -through the takeoff process, and---assuming no incorrect input--- -is entirely out of the hands of the estimator doing the "takeoff". -Other notes describe how a centralized system -separates the concerns of adjustment factors -and data input for individual projects. - -The "takeoff" workflow then is not about progressively approaching the target -price as with item-oriented methods, -but reducing the range of possible target prices, -reducing the risk of the estimate. - -Abandoning an item-oriented estimate -at any point before 100% completion -results in effectively 100% wasted effort. -In contrast, an abandoned risk-oriented estimate -becomes a budget with no additional effort. diff --git a/standalone-systems-takeoff.md b/standalone-systems-takeoff.md index a62759a..f96d5b4 100644 --- a/standalone-systems-takeoff.md +++ b/standalone-systems-takeoff.md @@ -3,7 +3,7 @@ id: aliases: [] tags: - destiny/permanent - - occupational/takeoff/standalone-systems + - occupational/takeoff - status/draft - type/guide - authorship/original diff --git a/statistical-modeling-for-construction-estimating.md b/statistical-modeling-for-construction-estimating.md index f94d73f..a80d230 100644 --- a/statistical-modeling-for-construction-estimating.md +++ b/statistical-modeling-for-construction-estimating.md @@ -15,6 +15,22 @@ tags: Cross-topic of [[statistical-modeling]] and [[construction-estimating]]. +%% +## TALK + +This note should discuss the application of modeling in estimating, +including what is already common practice (e.g. average run lengths), +as well as the potential for more robust models. + +Models are useful where information is limited, +and where more precise methods would be suboptimal[^1]. + +[^1]: see [[risk-management-for-construction-estimating]]. + +Specific examples should generally be relegated to linked notes. + +%% + ## Bayesian Takeoff #### User Story diff --git a/subfeeds-takeoff.md b/subfeeds-takeoff.md index 23bee24..1950695 100644 --- a/subfeeds-takeoff.md +++ b/subfeeds-takeoff.md @@ -3,7 +3,7 @@ id: aliases: [] tags: - destiny/permanent - - occupational/takeoff/subfeeds + - occupational/takeoff - status/draft - type/guide - authorship/original diff --git a/switchgear-takeoff.md b/switchgear-takeoff.md index 3e86369..f873743 100644 --- a/switchgear-takeoff.md +++ b/switchgear-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/switchgear + - occupational/takeoff - status/draft - type/guide title: Switchgear diff --git a/telecom-takeoff.md b/telecom-takeoff.md index eb383cc..c18a443 100644 --- a/telecom-takeoff.md +++ b/telecom-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/telecom + - occupational/takeoff - status/draft - type/guide title: Telecom diff --git a/estimating-ethics.md b/transparency-in-construction-estimating.md similarity index 78% rename from estimating-ethics.md rename to transparency-in-construction-estimating.md index 170206b..63839bf 100644 --- a/estimating-ethics.md +++ b/transparency-in-construction-estimating.md @@ -1,16 +1,23 @@ --- id: aliases: [] +title: Transparency in Construction Estimating tags: - authorship/original - destiny/permanent - - status/incomplete + - status/not-started - topic/construction - topic/estimating - - type/philosophy -title: Estimating Ethics + - topic/transparency + - type/cross-topic --- -# Estimating Ethics +# Transparency in Construction Estimating + +Cross-topic of [[transparency]] and [[construction-estimating]]. + +## Estimating Ethics + +### Ethics for the Solicitor Contractors engaging in unethical bidding practices can quickly gain a reputation for doing so, @@ -24,15 +31,7 @@ To ensure a transparent bidding process, one must * maintain confidentiality of bid submissions, and * provide equal access to bidding information. -### Terms - -> [!info] Bid Shopping -> the practice of sharing a bidder's quote with other prospective vendors -> in order to solicit lower bids. -> The competing quote may be legitimate, fabricated, -> or a non-serious proposal from a colluding vendor. - -## Bad Bid Practice +### Ethics for the Bidder Deceptive proposal language is a quick way to get blacklisted. @@ -43,3 +42,11 @@ is particularly reprehensible. > * Not including consideration for voltage drop > * Including standard, line-voltage switching as "lighting control" > * Excluding all mechanical disconnects + +### Terms + +> [!info] Bid Shopping +> the practice of sharing a bidder's quote with other prospective vendors +> in order to solicit lower bids. +> The competing quote may be legitimate, fabricated, +> or a non-serious proposal from a colluding vendor. diff --git a/two-way-takeoff.md b/two-way-takeoff.md index 834df45..ded9873 100644 --- a/two-way-takeoff.md +++ b/two-way-takeoff.md @@ -7,7 +7,7 @@ aliases: tags: - authorship/original - destiny/permanent - - occupational/takeoff/standalone-systems + - occupational/takeoff - status/draft - type/guide title: Two-Way Takeoff @@ -33,9 +33,7 @@ title: Two-Way Takeoff * FCR to elevator lobbies * FCR to stairwells - **Count** = Number of boxes run to. Per drawings if shown, otherwise use the greater of: - * Count of elevators - * Count of stairwells + **Count** = Count of elevator lobbies or stairwells (match length) ## Vertical @@ -44,7 +42,7 @@ title: Two-Way Takeoff `FIRE ALARM & DAS SYSTEMS`/`TWO WAY COMMUNICATION ASSEMBLIES`/`2-WAY COMMUNICATION = 1" CONDUIT ...` * **Length** = 15ft * Count - * **Count** = _match Horizontal_ + * **Count** = match Horizontal ## Firefighter Phone System diff --git a/uncertainty-in-construction-estimating.md b/uncertainty-in-construction-estimating.md new file mode 100644 index 0000000..481e37f --- /dev/null +++ b/uncertainty-in-construction-estimating.md @@ -0,0 +1,62 @@ +--- +id: +aliases: [] +title: Uncertainty in Construction Estimating +tags: [] +--- +# Uncertainty in Construction Estimating + +Cross-topic of [[uncertainty]] and [[construction-estimating]]. + +This note is intended to be purely descriptive. +See [[actuarial-science-for-construction-estimating]] +and [[risk-management-for-construction-estimating]] +for strategy based on such uncertainty. + +%% +## TALK + +What do I mean that project cost is uncertain until the last invoice? + +What distributions exist +which are known, +which can never be known and must be estimated? + +[[bid-price-modeling]] + +*** + +With perfect information all outcomes are certain. + +There exists some distribution representing the range of possible costs for a project. +The remaining uncertainty represents ignorance of information an estimator can not feasibly obtain. + +*** + +Suppose the estimator has spent years on the bid, +running simulations, consulting experts, etc. + +Suppose the estimator has received a message from a time traveler +which details significant news events and commodity markets +for the duration of the project. + +Suppose the estimator is prescient and has observed the final cost of the project +as reported in the winning contractor's historicals. + +%% + +## Expected Value of Perfect Information + +[[uncertainty#Expected Value of Perfect Information]] + +%% + +an organization pays in estimator hours. +These hours have a direct cost in salary and benefits, +however the greater cost is the opportunity cost +of tying up an estimator who could otherwise be starting a new project. + +In many cases, the utility of doubled throughput +far outweighs the increased risk of individual bids. + +%% \ No newline at end of file diff --git a/uncertainty.md b/uncertainty.md index 584bf79..76b9d39 100644 --- a/uncertainty.md +++ b/uncertainty.md @@ -75,19 +75,6 @@ in order to gain access to perfect information. The perceived _value_ of decreased uncertainty must be weighed against its _cost_. -#### In Construction Estimating - -This concept provides the basis for the solution -of one or more [[open-problems-in-estimating]]. -To reduce [[risk]] in [[construction-estimating]], -an organization pays in estimator hours. -These hours have a direct cost in salary and benefits, -however the greater cost is the opportunity cost -of tying up an estimator who could otherwise be starting a new project. - -In many cases, the utility of doubled throughput -far outweighs the increased risk of individual bids. - ## Types of Uncertainty ### Aleatory Uncertainty diff --git a/units-takeoff.md b/units-takeoff.md index 16c7ffe..3f5339f 100644 --- a/units-takeoff.md +++ b/units-takeoff.md @@ -4,7 +4,7 @@ aliases: [] tags: - authorship/original - destiny/permanent - - occupational/takeoff/units + - occupational/takeoff - status/draft - type/guide title: Unit Takeoff