Stack

Name: Stack
Brand: STACK Construction Technologies
Rating: 4.5 (1410 reviews)

K-Ops is a construction management and collaboration platform. Connect field and office. Improve project delivery.

Est 2012|Raised $30K|118 Ref Customers

LinkedIn 8K|Website|Web traffic 160K|FTEs 126|HQ Cincinnati, Ohio, US

Published Oct 15, 2026

01Common complaints

- If the primary need is PDF review and markup without integrated estimating, dedicated markup tools may be more economical. - If the organization is highly price-sensitive or has irregular estimating volume, annual per-seat pricing and renewal practices may be problematic. - If reliable offline access is required due to limited internet connectivity in typical work locations. - If regulated-industry buyers require public, detailed compliance artifacts (SOC 2 Type II, ISO 27001) without initiating a vendor security review. - If there are serious concerns about support and refund practices; public complaint samples warrant careful contract and reference checks.

Deal disqualifiers (poor fit)

Organizations that require robust offline capability or frequently operate in low-connectivity environments.
Buyers that only require PDF markup/measurement functionality; dedicated markup tools may be more cost-effective.
Organizations with highly specialized estimating assemblies that are not supported out of the box and that lack the resources to configure templates.

Known limitations evidenced in reviews

Internet dependency: occasional connection issues that restrict access to web-based data.
Measurement snapping or line interference: some users report needing to hide lines to avoid unwanted auto-connecting behavior.
Trade-specific assembly gaps: certain verticals may need to create assemblies from scratch.

Roadmap / future features

Vendor materials reference AI features and trade-specific tools; specific roadmap timelines and detailed release notes are not publicly documented in the materials reviewed.

Security/compliance gaps (public documentation)

SOC 2 is referenced by the vendor, but detailed public attestations, scope, and hosting/data residency disclosures are limited in the reviewed sources.

02Why they buy

Unique selling points supported by customer feedback

Ease of use and an intuitive workflow are frequently cited in user reviews.
An integrated takeoff and estimating workflow that reduces the need to export/import between multiple tools is a commonly referenced benefit.

Unique selling points that require validation

Security posture signaled by external scores and SOC 2 statements: these are useful signals but should be validated with audit artifacts and security questionnaires.
AI-assisted takeoff time-savings: reported percentages originate from vendor or partner materials and should be validated against buyer-specific datasets and drawing types.

Areas where competitors may have advantage

Deep PDF tooling and collaboration familiarity for teams focused on document markup.
Ecosystem alignment (e.g., Autodesk) for organizations that already use those platforms.

Why customers chose STACK (recurring reasons)

Ease of use and an intuitive user interface are frequently cited in reviews.
Centralization of plan sets, takeoff, and estimate outputs in a single tool is a commonly referenced benefit.
Cloud access and collaboration features are noted as benefits, with the tradeoff of connectivity dependency.

03Field reports

Review-platform sentiment snapshot (what’s accessible)

- G2: vendor profile and product pages show generally above-average scores across multiple review metrics. - Capterra: multiple pages indicate a sizable review base and generally positive value-for-money indicators on the platform. - TrustRadius: some product pages show limited review volume for certain modules; pricing references are present on listing pages. - Trustpilot: a small sample of reviews includes low scores and complaints about support and refund handling; while the sample is limited, the seriousness of some allegations is notable.

Direct quotes (positive and negative)

From public review excerpts across platforms: - Positive (ease of use): reviewers describe the product as fast and convenient to use. - Positive (long-term usability): some reviewers report multi-year usage and describe the product as intuitive and easy to use. - Negative (cloud dependency): some users report connection issues that affect access to data. - Negative (measurement UX): feedback includes instances where measuring can auto-connect to prior measurements unless lines are hidden. - Negative (trade fit / assemblies): reviewers in some trades (e.g., landscaping) report that organic or curved shapes can be time-consuming and that certain assemblies are not available by default. - Negative (support/refund concerns): a small number of external reviews allege poor support responsiveness and refund difficulties; details are limited in public snippets.

Why some customers left / considered leaving

Price increases and perceived lack of value as feature sets expanded.
Internet/connectivity dependency for web-based access.
Trade-specific limitations that required custom assembly creation.
Support and refund disputes reported in a small number of public reviews.

Vendor-highlighted outcomes (verify independently)

The vendor presents a customer case claiming substantial productivity improvements (described using percentage figures). Methodology details (baseline, measurement period, and definitions) are not provided in the public material and should be validated via customer reference checks.

AI takeoff claims (STACK Assist)

Media and partner reposts describe AI-assisted features and report claimed time savings. These accounts appear to originate from vendor or partner communications; independent benchmarking is recommended to validate claims against the buyer’s plan types, project scales, and trade-specific assemblies.

04Best fit

Company sizes

Based on vendor positioning and review-platform signals:

Small to mid-sized firms are a plausible core range, with the strongest fit being organizations that have at least a small team of estimators or preconstruction users performing recurring bids.
Larger organizations may also use STACK but will typically request SSO/API support and a formal security review.

Industries / verticals

General construction estimating and specialty trades (e.g., roofing, concrete, MEP), with vendor materials addressing multiple trades.

Roles and personas

Decision makers: owners, vice presidents of operations, preconstruction directors, estimating managers.
End users: estimators, bid coordinators, project managers, document controllers.

Qualification criteria (appropriate fit)

Organizations that require cloud-based takeoff and estimating without managing desktop installs.
Teams that need consistent estimating libraries and assemblies across multiple users.
Teams that value vendor-provided training resources and defined workflows.

05The pitch

What the product does (core value proposition)

STACK is a cloud-based construction preconstruction platform focused on digital quantity takeoff and estimating/proposals from plan sets (PDF drawings), with adjacent tools for field/document collaboration (STACK Build & Operate) and other workflow add-ons. Primary intended benefits include reduced time on takeoffs, more consistent estimates, and improved bid throughput. Key functional pillars (as described by the vendor): - Plan & spec management (organize, search, compare plan versions) - Quantity takeoff (digital measurements/counts) - Estimating & proposals (items/assemblies, cost data, proposal outputs) - Field collaboration / markup / issues / punch lists via Build & Operate

Target market and positioning

STACK is positioned for:

Estimators and preconstruction teams at subcontractors and general contractors
Firms that need standardized takeoff/estimating across multiple users and projects
Teams that prefer cloud-based workflows rather than desktop-only tools

Review and directory language across platforms commonly indicates STACK is used by SMB to mid-market construction teams doing recurring takeoffs/estimates rather than one-off projects.

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