# Roofing Ventilation Calculator vs OC Now

The clearest difference is rating: OC Now at 3.3 against Roofing Ventilation Calculator's 3.0. Roofing Ventilation Calculator's advantage is update cadence (every 3 months vs every 9 months) and device support (3 vs 1). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

OC Now holds the better App Store score, 3.3 against 3.0. Both are backed by a comparable volume of ratings — 6 and 4 respectively.

Roofing Ventilation Calculator ships an update every 3 months, OC Now every 9 months. The most recent releases landed on June 19, 2026 and June 3, 2026 respectively.

## The numbers

| Metric | Roofing Ventilation Calculator | OC Now |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.0 (6 ratings)](https://appshunter.io/ios/app/roofing-ventilation-calculator/id1035643148/reviews) | **[3.3 (4 ratings)](https://appshunter.io/ios/app/oc-now/id1453775492/reviews)** |
| Number of ratings | **6** | 4 |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 9 months |
| Monetization | Free | Free |
| Size | 34 MB | 113 MB |
| Requires iOS | **13.0** | 16.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Compagnie de Saint-Gobain](https://appshunter.io/developer/543924473) | [Owens Corning Sales, LLC](https://appshunter.io/developer/526596199) |

## What reviewers say

### Roofing Ventilation Calculator

[App page](https://appshunter.io/ios/app/roofing-ventilation-calculator/id1035643148)

Calculate the necessary amount of ventilation products for an attic space. Input attic dimensions or square footage to receive results based on the NFA 1/300 rule for balanced ventilation.

**Highlights:** Attic dimension input, Square footage input, NFA 1/300 rule calculation, Ventilation product quantity determination, Balanced ventilation planning

**Features:** macOS Compatibility

**In-app purchases:** none


### OC Now

[App page](https://appshunter.io/ios/app/oc-now/id1453775492)

Stay informed with instant company news and updates on your smartphone. Receive personalized notifications and share content with your team. This social platform keeps you connected to the latest stories and information.

**Highlights:** Instant company news updates, Personalized notifications, On-the-go stories, Content sharing with team, Like photos and videos

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Roofing Ventilation Calculator free?

Roofing Ventilation Calculator is free to download, with no in-app purchases.

### Is OC Now free?

OC Now is free to download, with no in-app purchases.

### Which has better reviews, Roofing Ventilation Calculator or OC Now?

OC Now is rated higher. Roofing Ventilation Calculator averages 3.0 out of 5 from 6 ratings, while OC Now averages 3.3 from 4 ratings.

### Do Roofing Ventilation Calculator or OC Now have ads?

Neither Roofing Ventilation Calculator nor OC Now shows ads.

### Which is updated more often, Roofing Ventilation Calculator or OC Now?

Roofing Ventilation Calculator ships an update every 3 months, and OC Now every 9 months. Most recently, Roofing Ventilation Calculator was updated on June 19, 2026 and OC Now on June 3, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*